Disagreement emerged at a Group of 20 (G20) summit on Tuesday as the United States and its allies backed a resolution condemning Russia's invasion of Ukraine, which Russia's foreign minister dismissed as unwarranted politicisation.

The summit on the Indonesian island of Bali is the first G20 leaders' meeting since Russia sent its troops into Ukraine in February.

The war, which Russia has described as a "special military operation", has overshadowed the meeting despite calls from host Indonesia for unity and a focus on action to resolve global economic problems like inflation, and food and energy security.

"Most members strongly condemned the war in Ukraine and stressed it is causing immense human suffering and exacerbating existing fragilities in the global economy," a 16-page draft declaration said, according to a copy seen by Reuters.

"There were other views and different assessments of the situation and sanctions," said the draft, which diplomats said had yet to be adopted by the leaders.

Russian Foreign Minister Sergei Lavrov, who is heading his country's delegation in the absence of President Vladimir Putin, denounced the attempt to condemn Russia as politicisation by Western countries that had tried unsuccessfully to include it in the declaration.

U.S. President Joe Biden, left, and India Prime Minister Narendra Modi, right

Lavrov said Russia had put forward an alternative view and the draft would be completed on Wednesday.

A U.S. official said earlier the United States expected the G20 to condemn Russia's war in Ukraine and its impact on the global economy.

German Chancellor Olaf Scholz said there were encouraging signs of a consensus that Russia's war against Ukraine was not acceptable.

G20 ministers' gatherings in the past have failed to produce joint declarations due to disagreement between Russia and other members on language, including on how to describe the war in Ukraine.

Earlier, Ukrainian President Volodymyr Zelenskiy told the summit in a virtual address that now was the time to stop Russia's war in his country under a plan he has proposed "justly and on the basis of the U.N. Charter and international law".

He called for restoring "radiation safety" with regard to the Zaporizhzhia nuclear power plant, introducing price restrictions on Russian energy resources, and expanding a grain export initiative.

"Please choose your path for leadership - and together we will surely implement the peace formula," he said.

Lavrov, who dismissed a news agency report on Monday that he had been taken to hospital in Bali with a heart condition, said he had listened to Zelenskiy's address, adding that the Ukrainian leader was dragging out the conflict and not listening to Western advice.

Russia's invasion of Ukraine triggered calls by some Western leaders for a boycott of the summit and for the withdrawal of Putin's invitation but Indonesia refused to do so.

Russia said earlier Putin was too busy to attend the summit and Lavrov was taking his place.