Russia said Thursday it will strongly oppose any bid to give Syria's UN seat to the rebel coalition fighting President Bashar al-Assad.

Russia's UN envoy Vitaly Churkin said recognizing the Syrian National Coalition would "undercut the standing of the UN."

Churkin reaffirmed Russia's condemnation of the Arab League for naming the coalition as the legitimate government and said the League was now playing a "negative" role in the two-year-old Syrian conflict.

The Arab League on Tuesday recognized the coalition and diplomats say Arab nations are now planning a campaign to give Syria's place at the 193-member United Nations to the opposition.

No formal move is expected however before the new UN General Assembly year starts in September. Russia, Assad's main international backer, is a current member of the General Assembly's credentials committee, which would make a recommendation to the full assembly on Syria's membership.

"We will oppose it very strongly, but you know I don't think it is going to happen," Churkin told reporters.

He said most UN states are "responsible" members, noting: "They value this institution, they understand that if something of the sort were to happen, that would really undercut the standing of the United Nations."

"You do not simply seat opposition groups who have gone through no proper process of legitimization and say well now they are the representatives of Syria," Churkin added.

"I think that this kind of a motion would not find very much support in the United Nations. And I think most of the countries are smart enough to understand that if they were to go down that road they themselves might be the target of such manipulation in the future," he added.

The Russian ambassador said the Arab League move had "undercut the efforts" of UN-Arab League peace envoy Lakhdar Brahimi and "damages" the League's standing.

"In fact they are beginning to act more and more as a negative rather than a positive force," he said.

Russia has repeatedly blocked UN Security Council efforts to increase pressure on Assad over the conflict, which the UN says has left more than 70,000 dead.