Paris (CNN) -- U.S. Secretary of State John Kerry said Sunday that Saudi Arabia will support military intervention in Syria by the United States and its partners.
"They have supported the strike and they support taking action," Kerry said after a long meeting of Arab League ministers originally called to discuss the Mideast peace initiative. "They believe that it's very important to do that."
Kerry told reporters he had a very good side meeting with Saudi Foreign Minister Saud al-Faisal, and Saudi Arabia was one of the countries to sign on to a statement condemning the reported use of chemical weapons last month by the Syrian military against rebels.
Saudi Arabia is a diplomatic heavyweight in the Arab world but hasn't publicly called for an international military reprisal after the incident.
With its vast air force and bases, Saudi Arabia could offer a lot of resources to Western militaries.
But it's not expected to participate directly in any attack on Syria, because that would be likely to inflame a widespread Arabian Peninsula antipathy against Western military forces intruding into Arab affairs.
Kerry also said the Arab League ministers unanimously condemned the August 21 incident.
"As we discussed today, all of us agreed -- not one dissenter -- that (Syrian President Bashar) al-Assad's deplorable use of chemical weapons -- which we know killed hundreds of innocent people, including at least 426 children on this occasion, this one occasion -- this crosses an international, global red line," he said.
He said the foreign ministers discussed the "possible and necessary measures" needed to deter al-Assad from using chemical weapons again. Kerry said a "number of countries immediately signed on" to an agreement reached by 12 countries on the side at the recent G20 summit.
And while he named Saudi Arabia as one of those nations, he said the others that had agreed to help would make their announcements in the next day.
The statement called for a "strong international response" and "supports efforts undertaken by the United States and other countries to reinforce the prohibition on the use of chemical weapons." It did not expressly endorse military action, although U.S. officials said the nations who signed it interpreted the statement as tacit support for strikes.
The Syrian government has denied being behind chemical weapons attacks, which it blames on rebels. Al-Assad on Sunday denied again he had anything to do with the use of chemical agents, U.S. journalist Charlie Rose reported. The PBS anchor and CBS "This Morning" co-host said al-Assad told him during an interview to be broadcast Monday that Syria was prepared to retaliate if there was a military strike by the United States and its partners.
"It doesn't surprise us that someone who would kill thousands of his own people, including hundreds of children, with poison gas would also lie about it," a spokeswoman for the National Security Council, Bernadette Meehan, said.
Al-Assad's rare interview with U.S. media comes as U.S. President Barack Obama lobbies Congress and the country to support military action.
Congress officially returns to Washington Monday after a monthlong summer recess to debate and vote on a resolution giving Obama the authorization to take military action.
The president will go to Capitol Hill on Tuesday and make his case to Senate Democrats, a Senate leadership aide said Sunday.
Obama will also address the nation on Syria Tuesday at 9 p.m. ET from the White House.
Videos that purport to show the results of a chemical weapons attack are part of a White House campaign to inform Congress about the nature of the incident, Kerry said.
"The reason for this is to make sure everybody understands what is at stake," he said. "Those videos make it clear to people that these are real human beings, real children, parents being affected in ways that are unacceptable to anybody, anywhere, by any standard."
He said a vast majority of the members are undecided as to how they will vote on authorizing force against Syria.
Qatari Foreign Minister Khalid bin Mohamed al-Attiyah appeared at the news conference with Kerry.
"Qatar is currently studying with its friends and the United Nations what it could provide in order to protect the Syrian people," he said, according to a translator.
Kerry met later with UK Foreign Secretary William Hague in London on Sunday. Britain's Parliament has ruled out getting militarily involved in Syria, but Prime Minister David Cameron has pledged to continue to push for a tough response against the al-Assad regime.
Kerry's efforts with European allies paralleled those of his boss, Obama, who tried to rally members of the G20 in St. Petersburg, Russia, last week.
Obama met with his Russian counterpart, President Vladimir Putin, on the sidelines of the St. Petersburg summit Friday. But despite both saying the talks were constructive, there was no sign of consensus.
CNN's Elise Labott reported from Paris. CNN's Steve Almasy reported and wrote from Atlanta. CNN's Nic Robertson, Nick Paton Walsh and Kevin Liptak contributed to this story.