BAGHDAD, Iraq (CNN) -- Iranian President Mahmoud Ahmadinejad has accepted an invitation to visit Baghdad, according to Iraq's Foreign Ministry.
Iraq's Nuri al-Maliki, left, and Iran's Mahmoud Ahmadinejad meet in Tehran, Iran, in August.
His visit would be the first trip to Iraq by an Iranian president since the nations fought an eight-year war that killed at least a million people in the 1980s.
If a date has been set for Ahmadinejad's visit, Iran has not disclosed it.
The Iranian president received the invitation when his Iraqi counterpart, Jalal Talabani, went to Tehran on an official trip, said Dr. Mahmoud Othman, a member of Iraq's parliament.
Relations between the countries have improved since the 2003 ouster of Saddam Hussein's Sunni-led regime in Iraq. Shiites make up a majority of the population in Iraq and Iran, and the two nations have cultural, religious and economic connections.
Iraqi Prime Minister Nuri al-Maliki paid a visit to Iran last year. U.S. and Iranian officials have met in Baghdad to discuss security concerns in Iraq. On February 6, Iranian and Iraqi trade officials are to meet in Iran for a conference.
Ahmadinejad's visit, if soon, would come at a time when the United States is pushing for fresh sanctions against Iran over its nuclear program.
Meanwhile, a top police official in the northern Iraqi city of Mosul and two other Iraqi officers were killed Thursday by a suicide bomber wearing a police uniform, Iraqi and U.S. authorities said.
Brig. Gen. Saleh al-Jubouri, the Nineveh province police director, was slain as he inspected the site of a massive, deadly blast the day before.
One of the dead was al-Jubouri's personal escort, police said.
The attack prompted police to impose a curfew in the city, which is the Nineveh provincial seat and the largest metropolis in northern Iraq. They also tightened security in the region, rocked by the Wednesday blast that killed 34 people and wounded 224 others.
"This cowardly behavior is yet another example of the AQI's [al Qaeda in Iraq's] complete disregard for human life and another attempt to take down the legitimate Iraqi security forces," a U.S. military statement said.
The U.S. military also confirmed Thursday's deaths, and said an Iraqi soldier and a coalition soldier had been wounded in the strike, carried out by an "imposter wearing" an Iraqi police uniform.
Al-Maliki's office called the Wednesday blast a terror attack and a "heinous crime." Iraq's prime minister also labeled the bomber in Thursday's attack a "suicide monster."
He said the actions reflect desperation among terrorists who are losing ground to troops. Al-Maliki said he would send a delegation to Mosul to probe "this evil attack and to assess the reality of the security situation in the province," and another delegation to check on the wounded and the families of the slain.
Dureid Kashmoula, Nineveh's provincial governor, said al-Jubouri had been inspecting the scene in Zanjili, where a stockpile of weapons detonated in an uninhabited building on Wednesday. He was working on water and power restoration, Kashmoula said.
"These groups want to destroy Mosul and we will not let them," said Kashmoula. He announced three days of mourning in Mosul and requested emergency aid from Iraq's central government.
The U.S. military said the stockpile blew up as Iraqi soldiers were on a weapons raid in western Mosul.
U.S. Army spokesman Lt. Col. Michael Simmering said the stockpile included from 20,000 to "30,000 pounds of TNT-like material."
"All reports indicate that, as they were examining the site, the explosives detonated, resulting in the destruction of approximately a 100-meter area radius of the city," Simmering said.
Mosul police said the explosives-laden building was unoccupied and most of the people killed were in nearby buildings.
A CNN stringer reported that government buildings, houses, a college and a hospital are nearby. The blast shattered windows at the hospital. The U.S. military also said several cell phone towers were knocked out and some Iraqi soldiers were among the wounded.
No U.S. soldiers were killed in the blast.
Emergency crews transported scores of injured people to five hospitals. Some had to be treated on the street because the hospitals had been overwhelmed with patients.
Nineveh is one of the four northern Iraqi provinces where U.S. and Iraqi forces are carrying out Operation Iron Harvest, an offensive to root out insurgents. The others are Diyala, Tameem, and Salaheddin.
Also Thursday, a roadside bombing in central Baghdad killed two police officers and wounded six people, an Interior Ministry official said. The bombing, in Andalus Square, targeted a police patrol about 8 a.m. Three of the wounded were police and the other three were civilians.
A Baghdad academic was shot dead in western Baghdad on Wednesday, an Iraqi Interior Ministry official confirmed Thursday.
Munther Muhrej Radh, dean of Baghdad University's School of Dentistry, was gunned down while driving home. Professionals, including academics, have been targeted by insurgents during the nearly five-year-old war in Iraq. E-mail to a friend
CNN's Jomana Karadsheh contributed to this report.