France’s ambassador, François Delattre, told reporters that France supported the Japanese proposal.
“It is a way to avoid the death of the J.I.M.,” he said as he entered the meeting. “It is a way to give us time, to work hard and find a spirit of unity.”
The United States also supported the Japanese proposal, diplomats said.
There was no immediate word on whether Russia would support it as well. But Vassily A. Nebenzia, the Russian ambassador, said after the Security Council meeting on Thursday that “we are always willing to compromise and find common ground.”
That Thursday meeting was punctuated largely by mutual accusations of duplicity and insincerity between Russia and the Western powers over how to stop the use of chemical weapons — a war crime — in the nearly seven-year-old Syria conflict.
Russia, the Syrian government’s strongest ally, has objected to the investigating panel’s Oct. 27 report that found Syria forces were responsible for the April 4 sarin attack on the rebel-held village of Khan Sheikhoun.
The Russians said that the panel’s investigation was “nonsense,” and that renewal of its mandate would require improved methods of establishing culpability for chemical weapons attacks.
The United States and its principal allies have strongly defended the panel’s methods and accused Russia of shielding the Syrian government from responsibility for an atrocity. The United States ambassador, Nikki R. Haley, said Russia had effectively said it “accepts the use of chemical weapons in Syria.”