The United States put forward a draft resolution Monday following alleged toxic gas use in the rebel-held town of Douma that killed at least 40 people and prompted President Donald Trump to indicate that a decision could be taken imminently on US military action.
US Ambassador Nikki Haley told Security Council diplomats that the United States wanted a vote on the measure, even though Russia said it contained "some unacceptable elements."
Russia put forward its own proposal in January that has been rejected by Western powers who say it would give the Syrian government an upper hand over investigations on its territory.
"The United States is pushing for a vote tomorrow," said a Security Council diplomat. "The US position was that they were negotiating in good faith, but the world is watching for the council to act."
Experts were meeting to discuss the draft resolutions, but no vote was formally requested by late Monday.
The US push for a new inquiry came amid heightened tensions over possible US military action in Syria, with Trump saying "major decisions" would be taken within 48 hours.
"From what we hear now, I am afraid they are looking for a military option, which is very, very dangerous," Russia's UN Ambassador Vassily Nebenzia told reporters following an emergency council meeting.
Trump -- who last year launched a missile strike on a Syrian air base after sarin was used in the town of Khan Sheikhun -- warned after the latest accusations that there would be a "big price to pay."
Grave repercussions
During a stormy council meeting, the Russian ambassador warned that a US military strike against Syria could have "grave repercussions" and stressed that the use of chlorine or sarin had not been confirmed in the attack.
Haley urged the council to take action, but warned that the United States was ready to respond, with or without the United Nations.
"We have reached the moment when the world must see justice done," Haley said.
"History will record this as the moment when the Security Council either discharged its duty or demonstrated its utter and complete failure to protect the people of Syria.
"Either way, the United States will respond."
The Russian envoy said Moscow had told the United States that it would not allow its forces on the ground in Syria to be put at risk.
"Armed force under mendacious pretext against Syria, where, at the request of the legitimate government of a country, Russian troops have been deployed, could lead to grave repercussions," Nebenzia said.
Moscow and Damascus have fiercely denied that chemical weapons were used in Syria.
'Nothing is off the table'
Speaking at a cabinet meeting on Monday, Trump said he was meeting with military and other advisers and a decision would be made within 48 hours and might come as soon as the end of the day.
"Nothing is off the table," he said when asked if US military action was a possibility.
Washington earlier presented a draft resolution that would establish a new independent inquiry of chemical attacks in Syria, but diplomats said the measure was unlikely to win Moscow's support.
In November, Russia used its veto power at the council to block the renewal of a previous UN-led probe that found the Syrian air force had dropped sarin on the town of Khan Sheikhun in April last year.
It was an atrocious attack. This is about humanity. We're talking about humanity. It can't be allowed to happen. US President Donald Trump
France accused Russia of having a hand in the attack on Douma that drew global outrage.
"These attacks took place either with Russia's tacit or explicit agreement, or despite its military presence on the ground," said French Ambassador Francois Delattre.
The suspected chemical weapons attack late on Saturday night killed at least 60 people had been killed and more than 1000 injured in several sites in Douma, a city near the capital Damascus, according to a Syrian aid organisation.
"It was an atrocious attack. Trump said. "This is about humanity. We're talking about humanity. It can't be allowed to happen," he said.
Asked if Russian President Vladimir Putin bore any responsibility for the attack, Trump said, "He may, yeah, he may. And if he does it's going to be very tough, very tough."
The Syrian government and its ally Russia have denied involvement in the attack.
