WASHINGTON (MarketWatch) — A rift over Syria between President Barack Obama and Russian President Vladimir Putin deepened after the two met on the sidelines of a G-20 summit and as Putin vowed to continue with aid to Syria.

Addressing reporters in St. Petersburg, Russia, Putin said Russia will keep selling arms to Syria and aiding the country if the U.S. goes ahead with a military strike.

Putin said about his meeting with Obama: “He doesn’t agree with me, I don’t agree with him, but we listened to each other.”

Stocks initially slumped on Putin’s remarks about aid to Syria but later erased those losses.

Obama, speaking after Putin, said he had a “candid” discussion with the Russian leader at the summit. But it was clear that Obama wasn’t swayed by the Russian leader’s opposition to striking Syria in retaliation for what the U.S. says was a chemical weapons attack that killed more than 1,000 people.

“There are times where we have to make hard choices if we’re going stand up for the things that we care about,” he said. “And I believe that this is one of those times.”

See streaming coverage of the Syrian crisis.

Obama said he would address the American public from the White House on Tuesday. He is facing skeptical voters and members of Congress as the U.S. prepares for a strike.

Obama is seeking congressional authorization for a strike on Syria. But the administration has made it clear it can take action without lawmakers’ approval.

“I will make the best case that I can to the American people, as well as to the international community, for taking necessary and appropriate action,” he said.

Putin’s comments hit shortly after the latest U.S. payrolls report, a softer-than-expected print showing 169,000 jobs added in August and downward revisions in prior months.

U.S. stocks tumbled after Putin’s remarks, with the Dow Jones Industrial Average DJIA, -0.46% falling as much as 148 point before recovering. Oil prices, meanwhile, climbed to above $110.

On Friday, Obama said he urged Putin to set aside differences with the U.S. and try to help with a political transition in Syria.