Russian Foreign Minister Sergei Lavrov walked out of a Group of 20 session as his German counterpart Annalena Baerbock was criticising Moscow over the Ukraine war, diplomats said.

Diplomats said Mr Lavrov later also left an afternoon session before a virtual appearance by Ukraine's foreign minister and was not present as US Secretary of State Antony Blinken condemned Russia in the closed-door meeting in Bali.

Ms Baerbock criticised Moscow for blocking dialogue with international partners.

Speaking to German television she said Mr Lavrov "left the first session halfway through" and skipped a second session "which shows even more clearly that he's not interested in international cooperation or dialogue with the other G19 partners".

"It underscores that the Russian government is not showing a millimetre of willingness to talk, particularly on the important question of how we will grapple with the global food crisis," she said.

Ms Baerbock said although the remaining 19 countries had differing views on "Russia's war of aggression", they were "very clear in appealing to Russia that this war must end".

"The majority of the countries made clear that Russia has the responsibility to immediately stop the bombing," she said.

The United States and Western allies pressured Russia at the talks in Indonesia over its "unprovoked and unjustifiable war of choice" in Ukraine, but Moscow's envoy remained defiant.

Mr Blinken met his French and German counterparts and a senior British official to discuss "Russia's unprovoked and unjustifiable war of choice" in Ukraine, the State Department said in a statement.

They "reviewed ways to address the global food security concerns that have resulted from Russia's deliberate targeting of Ukrainian agriculture", it said.

Antony Blinken is greeted by Indonesian Foreign Minister Retno Marsudi

The gathering was overshadowed by the fatal shooting of former Japanese Prime Minister Shinzo Abe at a campaign event.

Indonesian Foreign Minister Retno Marsudi, chair of the meeting, said Jakarta conveyed its "deepest sympathies" to Japan.

Before the news emerged, she addressed the war in a speech to the ministers including Mr Lavrov.

"It is our responsibility to end the war sooner than later and settle our differences at the negotiating table, not the battlefield," Ms Marsudi said.

In the session that followed, there was strong and "nearly unanimous" condemnation of Russia, a source in the meeting told AFP.

A US official indicated Washington did not want to embarrass Indonesia at the meeting by walking out on Mr Lavrov.

The hosts have addressed US concerns about Mr Lavrov attending in part by inviting Ukrainian President Volodymyr Zelensky to the G20 summit later this year and Foreign Minister Dmytro Kuleba to today's meet.

But there will be no family photo of the G20 ministers as is customary, an Indonesian government official said.

Mr Blinken arrived at the Mulia hotel this morning where he could be seen talking with South Africa's foreign minister before entering the same room as Mr Lavrov, who he last met in January.

Russia's top diplomat was seated between the Saudi Arabian and Mexican foreign ministers as the meeting began.

Sergei Lavrov was seated between the Saudi Arabian and Mexican ministers

He was later seen strolling and chatting to Indian Foreign Minister Subrahmanyam Jaishankar before he met with Mr Blinken.

In his meeting with Delhi's envoy, Mr Blinken said many of the G20 member countries had criticised Moscow over its campaign in Ukraine.

"What we've heard today already, is a strong chorus from around the world... about the need for the aggression to end," he said.

Today's meeting is a prelude to the leaders' summit on Bali in November that was meant to focus on the global recovery from the Covid-19 pandemic.

Mr Blinken's efforts to have a powerful Western stance against Russia at the meeting were diluted after British Foreign Minister Liz Truss pulled out following Prime Minister Boris Johnson's resignation as leader of his party yesterday.

She flew out of Bali this morning and was replaced by former British ambassador to the European Union Tim Barrow, a British official said.

While in Bali, Mr Blinken will also seek to reopen dialogue with Beijing in talks tomorrow with his Chinese counterpart Wang Yi, the first in months after tensions became strained over issues including Taiwan.

The meeting comes as US President Joe Biden voices hope for a conversation in the coming weeks with Chinese President Xi Jinping, with whom he last spoke in March.

Mr Lavrov met Mr Wang yesterday to discuss Russia's invasion, which Moscow says it launched to stop Ukraine from joining the NATO military alliance.

The United States has condemned Beijing's support for Russia, and Mr Blinken is expected to reiterate those warnings in talks with Mr Wang.

Australian Foreign Minister Penny Wong will herself meet Mr Wang on the sidelines of the meeting to press China to end trade "blockages", she said.