Leaders of the Group of 20 (G20) nations deplored Russia's aggression in Ukraine "in the strongest terms" on Wednesday and demanded its unconditional withdrawal in a declaration adopted at the end of a two-day summit.

The leaders of the world's biggest economies also agreed to pace interest rate rises carefully to avoid spillovers and warned of "increased volatility" in currency moves but it was Ukraine that dominated the summit on the Indonesian island of Bali.

"Most members strongly condemned the war in Ukraine," the leaders said in their declaration, signalling that Russia, which is a member of G20, opposed the wording.

The declaration recognised that "there were other views and different assessments of the situation and sanctions" but three diplomats said it was unanimously adopted.

The G20 leaders also said in the declaration that the use or threat of use of nuclear weapons was "inadmissible".

"It is essential to uphold international law and the multilateral system that safeguards peace and stability. This includes defending all the purposes and principles enshrined in the Charter of the United Nations and adhering to international humanitarian law," they said.

The president of host Indonesia, Joko Widodo, said the Ukraine war had been the most contentious issue.

"The discussion on this was very, very tough and by the end the G20 leaders agreed on the content of the declaration, which was the condemnation of the war in Ukraine because it has violated country borders and integrity," he said.

The Chinese government had no immediate comment on the declaration but its state media published a translation of it in Chinese.

EMERGENCY MEETING

Earlier, the day's schedule at the summit was disrupted by an emergency meeting to discuss reports on Tuesday of a missile landing in Polish territory near Ukraine and killing two people.

U.S. President Joe Biden said the United States and its NATO allies were investigating the blast but early information suggested it may not have been caused by a missile fired from Russia.

Taking a break from the negotiations, the G20 leaders dressed in white shirts, some with baseball caps with the G20 logo, and took part in a ceremony to plant mangrove saplings to signal the battle against climate change.

They agreed to pursue efforts to limit the rise in global temperatures to 1.5C, including speeding up efforts to phase down unabated use of coal.

Biden and Chinese leader Xi Jinping, in talks on the eve of the summit on Monday, agreed to resume cooperation on climate change.

On the sidelines of the summit, U.S. Treasury Secretary Janet Yellen held a two-hour meeting with Chinese central bank Governor Yi Gang, her first in-person talks with a senior Chinese economic official.

She had said before the meeting she hoped to get new insight into China's policy plans and work towards more economic engagement between the two countries.

WTO Director-General Ngozi Okonjo-Iweala told Reuters that several major economies faced a real risk of sliding into recession as the war in Ukraine, rising food and fuel costs, and soaring inflation cloud the global outlook.

'CALIBRATE TIGHTENING'

But it was the Western-led push to condemn Russia over its invasion of Ukraine that dominated the talks.

Many participants said President Vladimir Putin's Feb. 24 invasion of Ukraine had pummelled the global economy and revived Cold War-era geopolitical divisions just as the world was emerging from the worst of the COVID-19 pandemic.

Russia, whose forces pounded cities and energy facilities across Ukraine on Tuesday as the G20 met, has said "politicisation" of the summit was unfair.

"Yes, there is a war going on in Ukraine, a hybrid war that the West has unleashed and been preparing for years," Foreign Minister Sergei Lavrov said on Tuesday, repeating Putin's line that NATO's expansion had threatened Russia.

Lavrov was representing Putin at the summit but left on Tuesday evening. Russia was later represented by Finance Minister Anton Siluanov.

The West has accused Russia of making irresponsible statements on the possible use of nuclear weapons since its invasion of Ukraine. Russia has in turn accused the West of "provocative" nuclear rhetoric.

The 19 countries in the G20 together with the European Union account for more than 80% of the world's gross domestic product, 75% of international trade and 60% of its population.

In their declaration, the leaders said the world economy was facing "unparalleled multidimensional crises" ranging from the Ukraine war to a surge in inflation, forcing many central banks to tighten monetary policy.

As well as agreeing to calibrate tightening, the G20 leaders reaffirmed their commitment to avoid excessive exchange-rate volatility while recognising that "many currencies have moved significantly" this year.

On debt, they voiced concern about the "deteriorating" situation of some middle-income countries and stressed the importance of all creditors sharing a fair burden.

(Reporting by Fransiska Nangoy, Stanley Widianto, Nandita Bose, Leika Kihara, David Lawder and Simon Lewis in Nusa Dua, Andrea Shalal in Washington, Andreas Rinke in Berlin; Writing by Ed Davies; Editing by Raju Gopalakrishnan, Robert Birsel and Tom Hogue)