Matthew Lee, Associated Press?

Nancy Benac, Associated Press

GENEVA — Striking a tough tone, U.S. Secretary of State John Kerry opened swiftly convened talks with Russia on Syria’s chemical weapons Thursday by bluntly rejecting a Syrian pledge to begin a “standard process” by turning over information rather than weapons — and nothing immediately.

That won’t do, Kerry declared at an opening news conference, a stone-faced Russian Foreign Minister Sergey Lavrov at his side. “The words of the Syrian regime in our judgment are simply not enough.”

“This is not a game,” Kerry said of the latest developments in a series that has rapidly gone from deadly chemical attacks to threats of retaliatory U.S. air strikes to Syrian agreement with a Russian plan to turn over the weapons and, finally, to the crucial matter of working out the difficult details.

“We believe there is nothing standard about this process at this moment because of the way the regime has behaved,” Kerry declared. And he kept alive the threat of U.S. military action, saying the turnover of weapons must be complete, verifiable and timely — “and finally, there ought to [be] consequences if it doesn’t take place.”

Adding to the drama, Russian President Vladimir Putin weighed in from afar, raising eyebrows with an opinion piece in The New York Times that chided Americans for seeing themselves as “exceptional.” That was an apparent reference to a comment President Barack Obama made in his Syria speech Tuesday night, explaining why he felt the U.S. needed to take action. Congress has shown little inclination to authorize military action, and a vote on that has been put off.

Putin also warned that a U.S. strike against Syria because of chemical weapons use could unleash new terrorist attacks. And he still maintained there is “every reason to believe” the weapons were used by rebels and not by Assad’s military. In Washington, Obama’s spokesman said Russia was “isolated and alone” in that view.

Obama, for his part, said simply that he was hoping for “a concrete result” from the talks.

The back-and-forth was a stark indication of the challenging work ahead as Kerry, Lavrov and their teams of chemical-weapons experts plunge into talks aimed at finding an agreement on how to dismantle the chemical weapons amid the confusion and danger of Syria’s civil war.

Lavrov seemed to contradict Kerry’s negative view of Syrian President Bashar Assad’s offer to provide details on his country’s chemical arsenal beginning 30 days after it signs an international convention banning such weapons. Syria’s ambassador to the United Nations said that as of Thursday his country had become a full member of the treaty, which requires destruction of all chemical weapons.

Lavrov said the initiative must proceed “in strict compliance with the rules that are established by the Organization for the Prohibition of Chemical Weapons.” That suggests Russia does not agree with the U.S. that this is an exceptional case and that Syria should face tougher standards than other countries.

We proceed from the fact that the solution to this problem will make unnecessary any strike on the Syrian Arab Republic, and I am convinced that our American colleagues, as President Obama stated, are firmly convinced that we should follow a peaceful way of resolution to the conflict in Syria.” Lavrov said.

The distrust in U.S.-Russia relations was on display even in an offhand parting exchange at the news conference.

Just before it ended, Kerry asked the Russian translator to repeat part of Lavrov’s concluding remarks.

When it was clear that Kerry wasn’t going to get an immediate re-translation, Lavrov apparently tried to assure him that he hadn’t said anything controversial. “It was OK, John, don’t worry,” he said.

“You want me to take your word for it?” Kerry asked Lavrov. “It’s a little early for that.”

The meetings in Geneva got underway as Assad, in an interview with Russia’s Rossiya-24 TV, said his government would start submitting data on its chemical weapons stockpile a month after signing the convention. He also said the Russian proposal for securing the weapons could work only if the U.S. halted threats of military action.

But Kerry, who met earlier Thursday with Lakhdar Brahimi, the U.N.-Arab League envoy for Syria, made clear the threat remains.

“President Obama has been clear that should diplomacy fail, force might be necessary to deter and degrade Assad’s capacity to deliver these weapons,” he said. “It won’t get rid of them, but it could change his willingness to use them.”