Russia has urged the US to avoid taking military action in response to an alleged chemical attack in Syria.
“I would once again beseech you to refrain from the plans that you’re currently developing,” Moscow’s UN envoy Vasily Nebenzia said on Tuesday.
He warned Washington that it will “bear responsibility” for any “illegal military adventure” it carries out.
But Western leaders say they have agreed to work together to target those responsible for the attack in Douma.
French President Emmanuel Macron said any strikes would target Syrian government chemical facilities.
US President Donald Trump has promised a “forceful” response, and he and his Defence Secretary, James Mattis, have canceled travel plans this week.
Syrian opposition activists, rescue workers and medics say dozens of people died in a suspected chemical attack on the rebel-held town of Douma, in the Eastern Ghouta region.
President Bashar al-Assad’s government – which receives military backing from Russia – denies being behind any chemical attack.
What is the UN doing?
The warning from Moscow came during a divided meeting of the UN Security Council which failed to pass any measures to set up an inquiry into the alleged attack.
As permanent members of the council, Russia and the US both have the power to veto. They both blocked each other’s proposals to set up independent investigations.
The US-drafted resolution would have allowed investigators to apportion blame for the suspected attack, while Russia’s version would have left that to the Security Council.
A team from the Organisation for the Prohibition of Chemical Weapons (OPCW) is due to deploy to Syria “shortly” to determine whether banned weapons were used in Douma.
But the OPCW will not seek to establish who was responsible for the attack.
The UN session was the latest in a series of showdowns between Russia and the US and saw harsh words exchanged between the countries.
Mr. Nebenzia accused the US of “planting this resolution” as a “pretext” to justify military action.
“We could find ourselves on the threshold of some very sad and serious events,” he said.
US envoy Nikki Haley responded by calling the vote a “travesty”.
“Russia has trashed the credibility of the council,” she said.
“Whenever we propose anything meaningful on Syria, Russia vetoes it.”