UNITED NATIONS, Feb 28 (AFP) - Facing deepening isolation on the world stage, Russia faced a crucial test of support on Monday (Feb 28) as the 193 members of the UN General Assembly held an extraordinary debate on a resolution condemning Moscow's "aggression" in Ukraine.

During the rare emergency special session - just the 11th the Assembly has held in the United Nations' 77-year history - Russia defended its decision to invade its neighbour as member state after member state made a plea for peace.

"The fighting in Ukraine must stop," warned UN Secretary-General Antonio Guterres, after the session began with a minute of silence for the victims of the conflict.

"Enough is enough. Soldiers need to move back to their barracks. Leaders need to move to peace. Civilians must be protected," he pleaded.

Representatives of more than 100 countries were expected to speak as the global body decides if it will support the resolution that demands Russia immediately withdraws its troops from Ukraine.

The resolution is non-binding but will serve as marker of how isolated Russia is.

The wording of the resolution was watered down to try to attract maximum support, according to drafts seen by AFP. It no longer "condemns" in the strongest terms, Russia's aggression but rather "deplores" it.

A vote is expected on Wednesday. Its authors hope they may exceed 100 votes in favour - though countries including Syria, China, Cuba and India are expected to either support Russia or abstain.

It will be seen as a barometer of democracy in a world where autocratic sentiment has been on the rise, diplomats said, pointing to such regimes in Myanmar, Sudan, Mali, Burkina Faso, Venezuela, Nicaragua - and, of course, Russia.

"If Ukraine does not survive, the United Nations will not survive. Have no illusions," said Ukraine's ambassador to the UN, Sergiy Kyslytsya, imploring countries to support the resolution.

Russian ambassador Vassily Nebenzia reiterated Moscow's stance - flatly rejected by Kyiv and its Western allies - that its military operation was launched to protect residents of breakaway regions in eastern Ukraine.

"The hostilities were unleashed by Ukraine against its own residents," he said from the podium.

"Russia is seeking to end this war," Nebenzia added.