STORY HIGHLIGHTS
- NEW: The opposition says at least 175 people had been killed across Syria on Monday
- The U.S. calls the potential use of chemical weapons "completely unacceptable"
- Iraq opens border crossings to Syrian refugees
- Arab League offers Syria's president "a safe exit" if he quickly resigns, leaves country
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(CNN) -- The Syrian Foreign Ministry said Monday the country has chemical or biological weapons, but would never use them against its citizens -- only against foreign attackers.
"Any stocks of (weapons of mass destruction) or any unconventional weapon that the Syrian Arab Republic possesses would never be used against civilians or against the Syrian people during this crisis at any circumstance, no matter how the crisis would evolve," ministry spokesman Jihad Makdissi told reporters.
"All the stocks of these weapons that the Syrian Arab Republic possesses are monitored and guarded by the Syrian army. These weapons are meant to be used only and strictly in the event of external aggression against the Syrian Arab Republic," he said Monday.
The United States called for Syria to never use the weapons and keep them safely stored.
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"I think we've been absolutely clear where we stand on this issue, which is that any possible use of these kinds of weapons will be completely unacceptable," State Department spokeswoman Victoria Nuland said. "Any talk about any use of any kind of a weapon like that in this situation is horrific and chilling. The Syrian regime has a responsibility to the world, has a responsibility first and foremost to its own citizens to protect and safeguard those weapons."
Makdissi's remarks come after months of international chatter about whether foreign countries should intervene militarily to try to end more than a year of bloodshed in Syria. Another 175 people were killed around the country Monday, 90 of them in and around Damascus, opposition groups reported.
The dead included 25 people whose bodies were found in the Damascus neighborhood of al-Berzeh, the scene of heavy fighting between rebel forces and government troops, according to the Local Coordination Committees of Syria, a network of opposition activists. Another 24 bodies were found in the suburbs of the capital, the group said.
The LCCC and the Syrian Observatory for Human Rights also said several inmates were killed at a prison in Aleppo as guards tried to put down a days-old protest there. The LCC said nine prisoners were killed, while the London-based Syrian Observatory said 7 were killed and 16 wounded.
CNN cannot independently confirm reports of violence because the government restricts access by foreign journalists.
Meanwhile, the Arab League will offer Syrian President Bashar al-Assad "a safe exit" if he resigns quickly and leaves the country, a senior Arab League official said, marking the latest attempt to get Syria's longtime ruler to step down.
The official provided no further details because the source is not authorized to speak to the media.
Qatari Foreign Minister Sheikh Hamad bin Khalifa Al-Thani did not discuss an exit plan when speaking with reporters after the Sunday meeting, but confirmed "there is an agreement on the need for the swift resignation" of al-Assad.
"We call on the opposition and the Free Syrian Army to form a government of national unity," Sheikh Hamad said.
Despite the Arab League's proposal, the brutal violence has not let up. At least 30 people were killed Monday, the opposition Local Coordination Committees of Syria said.
See images of the showdown in Syria
The Arab League would not be the first to offer an outlet for al-Assad.
Tunisia -- the cradle of the Arab Spring uprisings and the first country last year to oust its longtime ruler -- offered asylum to the Syrian president in February in an attempt to spare further bloodshed.
And the daughter of Qatar's emir has suggested exile in Doha, according to a cache of e-mails leaked to CNN earlier this year.
If al-Assad were to leave, he would follow a series of longtime rulers in the region who have succumbed to popular revolts since last year, including former Egyptian President Hosni Mubarak, deposed Libyan dictator Moammar Gadhafi and former Yemeni President Ali Abdullah Saleh, who stepped down in a transfer-of-power deal.
Rime Allaf, an associate fellow at the Chatham House in London, said she thinks Syrians opposed to al-Assad are split on the notion of a "safe exit" for the president.
"Some may want a way to save as many lives as possible, so if he leaves without prosecution, then so be it, as they think the matter of most urgency now is saving the Syrian people," said Allaf, a Syrian national.

Rebel fighters load an anti-aircraft machine gun on an armored vehicle in Atareb, east of Syria's second-largest city, Aleppo, on Tuesday, July 31. Unrest spread across other volatile regions of the country as forces of President Bashar al-Assad's regime shelled targets and launched raids in and around Damascus, Homs, Daraa and Deir Ezzor.
Syrian boys run near a building hit by bullets and fire in Atareb.
A member of the Free Syrian Army fires at forces loyal to President Bashar Al-Assad in a district of Aleppo called Salah Edinne on Tuesday.
A member of the Free Syrian Army carries an injured civilian to safety in Aleppo's district of Salah Edinne on Tuesday.
Members of the Free Syrian Army learn that a tank belonging to forces loyal to President Bashar Al-Assad is heading to the area.
A Syrian boy carries bags of bread as people wait outside a bakery near Syria's second-largest city, Aleppo.
A photo released by Syrian Arab News Agency depicts damaged buildings in Homs on Monday, July 30.
A Free Syrian Army fighter takes position Sunday, July 29, in Aleppo as people flee shelling. Intense clashes have been under way for more than a week between the regime and rebels in Aleppo, Syria's commercial and cultural center.
Parts of Syria's largest city saw the fiercest clashes yet in the country's 16-month crisis on Saturday, July 28. About 200,000 people have fled fighting in Aleppo and surrounding areas in the past two days, a U.N. official says.
Fighting leaves vehicles damaged Saturday in the southwestern city of Daraa.
Syrians carry the body of a man allegedly killed in the bombardment of Sukari, southwest of Aleppo, by Syrian regime forces on July 27.
Destruction appears widespread in Homs on Friday, July 27, in a handout photo from the Syrian opposition Shaam News Network.
A Syrian opposition fighter takes aim during clashes with forces loyal to President Bashar al-Assad in Aleppo on Wednesday, July 25.
Family and friends mourn over the body of Usame Mircan, who they say was killed by a Syrian government sniper in Aleppo on Wednesday.
Usame Mircan's mother grieves after he was killed during fighting in Aleppo.
The bodies of men killed during clashes between Syrian rebel fighters and goverment forces lie on the Aleppo street on Thursday, July 26.
Fighters from the Syrian opposition rest at a former primary school in Aleppo on Wednesday.
Residents take cover as fighters from the Syrian opposition clash with forces loyal to President Bashar al-Assad in Aleppo on Wednesday.
Syrian rebels guard a checkpoint in Aleppo on Wednesday.
A damaged portrait of President Bashar al-Assad sits among piles of debris at a checkpoint manned by Syrian rebels in Aleppo on Wednesday.
Syrian rebels drive through Selehattin near Aleppo during clashes with government forces on Monday, July 23.
A Syrian rebel runs through the streets of Selehattin during an attack on a municipal building. The rebel Free Syrian Army says it is attempting to "liberate" several districts of Aleppo.
Syrian rebels work to find snipers during clashes Monday between the opposition and government forces in Selehattin.
Syrian rebels make their way down a street Monday in Selehattin near Aleppo. If they gain control of Aleppo, it would mark a pivotal point in the Syrian crisis.
Syrian rebels take cover behind sandbags during fighting Monday at the entrance to the city of Selehattin.
On Sunday, July 22, a Syrian refugee looks out from a bus as he arrives at a refugee camp in Turkey opposite the Syrian commercial crossing point Bab al-Hawa.
Syrian refugees flee from a refugee camp nicknamed "Container City" on the Turkish-Syrian border in Kilis province, southern Turkey, on Sunday.
A mortar shell falls toward the Syrian village of Jbatha Al-khashab, about 45 kilometers (28 miles) south of Damascus. It's seen from the Israeli side of the border, in the Golan Heights.
Smoke from artillery shelling rises above Jbatha Al-khashab.
An armed Syrian rebel wearing the jersey of FC Barcelona rests with comrades near the northern city of Aleppo on Sunday. The rebel Free Syrian Army announced the start of the battle to "liberate" Aleppo, Syria's commercial hub and a traditional bastion of President Bashar al-Assad's regime.
A Free Syrian Army soldier rips a portrait of President Bashar al-Assad at the Bab Al-Salam border crossing to Turkey on Sunday.
Dozens of Turkish truck drivers on Saturday, July 21, accused Free Syrian Army rebels of having burned and looted their lorries as they captured Syria's Bab al-Hawa post, near Aleppo, from government troops.
In this photo released by the Shaam News Network, a truck burns after shelling in the Erbeen suburb of Damascus on Saturday, July 21.
Refugees fleeing the violence in Syria arrive by bus in Baghdad, Iraq, on Saturday.
Turkish soldiers stand guard at the Cilvegozu border gate in Reyhanly that connects to Syria's Bab al-Hawa post. An estimated 120,000 people have fled Syria to Turkey, Iraq, Lebanon and Jordan.
Burned-out trucks at the Bab al-Hawa Syrian border post with Turkey on Friday, July 20. Syrian rebels seized control of the post after a fierce battle with Syrian troops, an AFP photographer at the scene reported.
Syrian soldiers celebrate in the al-Midan area in Damascus on Friday. Syrian regime forces routed rebel fighters from the Damascus neighbourhood of Midan, Syrian state television reported, saying troops had "cleaned" the district of "terrorists."
Journalists are shown a dead body on a government tour of the al-Midan area in Damascus on Friday.
Members of Syria security forces rest in the al-Midan area in Damascus on Friday.
Syrian army soldiers hang their national flag in a partially destroyed neighborhood in the al-Midan area in Damascus.
Smoke hangs in the air in a partially destroyed neighborhood in the al-Midan area in Damascus.
Members of Syria security forces pose for photographers in the al-Midan area in Damascus after driving out the rebel fighters.
Syrian residents take goods from a truck that rebels captured at the Bab al-Hawa border crossing with Turkey on Friday.
A picture released by the official Syrian Arab News Agency on July 19 shows Syrian General Fahd al-Freij meeting with President Bashar al-Assad in Damascus after his swearing-in ceremony as defense minister.
A man holds up a picture of President Bashar al-Assad at a former police station in Atareb after clashes between Syrian soldiers and Free Syrain Army near Aleppo on Thursday, July 19. Rebels seized control of border crossings with Iraq on Thursday, dealing a new blow to al-Assad, as China and Russia dismayed the West by blocking U.N. action against his regime.
People walk along the street in Atareb amidst damage caused by clashed between Syrian soldiers and the Free Syrian Army.
A Syrian man checks the former police station of Syrian regime after a clash at Atareb on Thursday.
Smoke ascends from from alleged shelling of the Syrian village of Jebata al-Khashab as seen from the hill village of Buqaata in the Israeli-annexed Golan Heights on Thursday.
The death toll in Syria on July 12 reached 287, making it the bloodiest day in Syria since the uprising began. As it has done consistently, Syrian state television blamed "armed terrorist groups" for the killings.
A Syrian woman sits with her grandson outside a damaged building after attacks in the Syrian village of Treimsa on July 13, 2012. More than 200 people were massacred in the town, according to activists.
A Syrian demonstrator holds an opposition flag during a protest in Damascus on July 2, 2012. There have been increasing reports of violence in the Syrian capital.
Syria's President Bashar al-Assad waves as he arrives for a speech to Syria's parliament in Damascus on June 3, 2012. The embattled president denied that government forces were behind the "outrageous" massacre in Houla.
People gather at a mass burial on May 26, 2012 for victims reportedly killed during an artillery barrage from Syrian forces in Houla. The attack left at least 108 people dead, including nearly 50 children, according to the United Nations.
Members of the Free Syrian Army return to Qusayr on May 12, 2012 after an attack on Syrian regime forces in the village of Nizareer, near the Lebanese border in Homs.
A U.N. observer speaks with Syrian rebels and civilians in the village of Azzara on May 4, 2012, days before the country's parlianemtary polls were held against a backdrop of unrest.
Thousands of Syrians wave their national flag and hold portraits of President Bashar al-Assad and Lebanon's Hezbollah chief Hassan Nasrallah, right, during a rally to show support for their leader on March 29, 2012 in Damascus.
Syrian rebel fighters man a checkpoint leading into the town of Taftanaz in the rebel stronghold province of Idlib on March 20, 2012.
A Free Syrian Army rebel mounts his steed in the Al-Shatouria village near the Turkish border in northwestern Syria on March 16, 2012, a year after the uprising began. The Free Syrian Army is an armed opposition group made up largely of military defectors.
Syrian refugees walk across a field before crossing into Turkey on March 14, 2012. International mediator Kofi Annan called for an immediate halt to the killing of civilians in Syria as he arrived in Turkey for talks on the crisis.
A day after the twin suicide bombings, Syrian mourners pray over the coffins of the 44 people killed during a mass funeral in Damascus.
A Syrian man who was wounded in a suicide attack rests at a hospital in Damascus on December 23, 2011. Suicide bombers hit two security service bases in the Syrian capital, killing dozens of people.
Arab foreign ministers attend an emergency meeting at the Arab League headquarters in Cairo on October 16, 2011, to discuss the crisis in Syria.
U.S. Secretary of State Hillary Clinton speaks to the media in Washington on August 18, 2011. Clinton said U.S. sanctions on Syrian oil "strike at the heart of the Syrian regime."
Syrian youths wave national flags while army troops drive out of Daraa on May 5, 2011. During a week-long military lockdown of the town, dozens of people were reportedly killed in what activists described as "indiscriminate" shelling on the city.
Syrians in Damascus protest in the street on March 25, 2011, after clashes with government forces in Daraa left several dead.
Supporters of Syrian President Bashar al-Assad rally on April 1 in Istanbul, Turkey, as delegates from dozens of countries gather to push for ways to end the deadly violence in Syria. The United Nations estimates more than 10,000 people have been killed since the beginning of the crisis in March 2011. The conflict is now being labeled a civil war by the International Committee of the Red Cross.
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Photos: Showdown in Syria
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"Others say it is impossible to let him leave. Not only would it let him get away with thousands of murders and the destruction of the country, but it also would give him a green light to keep on doing what's he's doing, knowing that when he decides to leave, he can leave."
Read more on preparing for al-Assad's exit
But Allaf said she thinks there is "absolutely zero" chance that the president will take up the Arab League's offer.
"I think Assad does not plan on ever accepting any possible plans for escaping or leaving," she said. "I think he will keep on fighting, hoping the revolution will stop."
The Syrian government has long maintained that "armed terrorist groups" are fueling violence in the country.
Responding to a question about clashes in Damascus, Makdissi said, "We are in a state of self-defense."
But he later added, "This is an exceptional matter. It will last a couple of days, and matters will return to normal."
On Monday, chaos ensued in cities across the country, opposition activists said.
In Homs, two people were killed "due to intense shelling by helicopters and rocket launchers, accompanied by intense clashes between the (rebel) Free Syrian Army and the regime army," the LCC said.
The LCC reported fierce clashes for a second day in Aleppo, Syria's largest city and commercial hub. In a video posted online Sunday, the head of the rebel Free Syrian Army in Aleppo announced an operation "to liberate the city of Aleppo from the rule of the Assad thugs, whose hands were blood-stained by heinous crimes against our people."
Brig. Gen. Abdel Jabbar Al-Obeidi also vowed to secure Aleppo and protect all minorities and sects, including the members of Alawite sect that the president belongs to.
If rebels eventually gain control of Aleppo, it would mark a pivotal point in the Syrian crisis and deal a heavy blow to al-Assad's financial ties.
The Syrian crisis started in March 2011, when a fierce government crackdown against protesters morphed into a nationwide uprising against the regime.
Video: How does Assad survive in Syria?
The United Nations estimates more than 10,000 people have been killed since the crisis began more than 16 months ago. But Rupert Colville, a spokesman for the office of the U.N. high commissioner for human rights, said the United Nations has not been giving out overall death toll numbers since December "because it became impossible to verify the numbers in any meaningful way."
Opposition groups tracking deaths have issued higher tolls. The LCC, for example, estimates more than 16,000 people -- mostly civilians -- have died.
In addition to the deaths, thousands of refugees have fled Syria into neighboring countries to escape the turmoil.
The three border crossings between Iraq and Syria were opened Monday to Syrian refugees, an Iraqi government spokesman said.
"The border guards, police and border provinces were guided to provide all the needed support to the Syrian refugees," Ali al-Dabbagh said in a written statement.
The United States will give Jordan $100 million in special economic aid to help ease the burden of hosting Syrian refugees, the U.S. Embassy in Jordan said Monday.
Read More: Why Syria could get even uglier
CNN's Mohamed Fadel Fahmy, Salma Abdelaziz, Schams Elwazer, Raja Razek and Mohammed Tawfeeq contributed to this report.