UN Security Council talks on Syria virtually collapsed Monday, leaving the major powers heading for a veto showdown on a proposal to impose sanctions on President Bashar al-Assad.
Russia will veto a western resolution linking the renewal of the UN mission with sanctions when it comes to a vote on Wednesday, its UN ambassador Vitaly Churkin said after council talks.
A rival Russian resolution just proposing to renew the UN mission would fail to get enough votes from the 15 council members to pass, US envoy Susan Rice told reporters. Russia is Assad's main ally.
The 90-day mandate of the UN Supervision Mission in Syria (UNSMIS) ends on Friday and if no resolution is passed by then it would have to shut down this weekend, diplomats said.
Rice said it would be "immoral" to leave the nearly 300 unarmed observers in Syria if the council was not going to pressure Assad to carry out the peace plan of UN-Arab League envoy Kofi Annan.
Russia's Foreign Minister Sergei Lavrov has accused the West of using "elements of blackmail" by trying to get Russia to agree to link sanctions to the renewal of the UNSMIS mandate.
Britain, France, United States, Germany and Portugal want a vote on their resolution -- proposing sanctions under Chapter 7 of the UN Charter -- on Wednesday.
"We will see, I made it very clear we are going to vote against this resolution," Russia's UN ambassador Vitaly Churkin told reporters after the latest tense talks between ambassadors of the 15-nation council.
A Russian vote against is a veto of any council resolution. Britain, China, France and the United States also have the veto power as permanent members.
Churkin said the only job of the council was to extend the UNSMIS mandate. "If people want to attach their individual political agendas, it means they do not want this mission to continue."
US envoy Rice countered that the rival Russian resolution would not get the required minimum number of votes to pass.
"I don't think there are nine votes for the Russian draft," she said
Rice, who has previously said the United States could block the extension of the UN mission, said that continuing UNSMIS was "questionable" as there is no ceasefire in Syria and no political process.
"Clearly continuing to do the same old thing is not working. The logic of the draft resolution that the British have tabled and which we strongly support is that there needs to be something new. There needs to be pressure applied under Chapter 7," the US envoy said.
Ambassadors are expected to meet again Tuesday, and China's envoy Li Baodong said he was trying to persuade both sides to put back a vote to allow more negotiating time.
The west appears determined to hold a vote on Wednesday however.
"There is clearly overwhelming support for the text," said Mark Lyall Grant, UN envoy for Britain, which took the lead writing the resolution.
"Russia and China still expressed objections to Chapter 7, but when challenged, they were unable to come up with any convincing reasons why," Lyall Grant added.
"Everyone else appeared to be happy with the text as is it is now emerging. So obviously we are happy to have further negotiations, we have scheduled a vote for Wednesday afternoon."
Lyall Grant said that "high level contacts" are being held between the major powers on the sanctions dispute.