Russian Foreign Minister Sergei Lavrov bitterly criticised Western nations over the Ukraine war, telling the United Nations that the US and its allies sought to "destroy" his country.

"The official Russophobia in the West is unprecedented. Now the scope is grotesque," Mr Lavrov said in a fiery UN General Assembly speech.

"They are not shying away from declaring the intent to inflict not only military defeat on our country but also to destroy and fracture Russia," he added.

After days of Western leaders denouncing Russia's invasion of Ukraine, Mr Lavrov used Russia's turn at the General Assembly rostrum to hit back at pressure on Moscow led by Washington.

The US, he said, was expanding the Monroe Doctrine - its 19th-century declaration of Latin America as its exclusive sphere of influence - and "trying to turn the entire world into its own backyard."

"Declaring themselves victorious in the Cold War, Washington erected themselves almost into an envoy of God on Earth, without any obligations but the sacred right to act with impunity wherever and wherever they want," he said.

He also defended referendums in Russian-occupied parts of Ukraine, describing them as people claiming land "where their ancestors have been living for hundreds of years".

"The West is now throwing a fit" on the referendums, Mr Lavrov said.

US President Joe Biden and other Western leaders have vowed never to accept results from the "sham" referendums, seeing them as part of an effort to change borders by force.

China calls on Russia and Ukraine not to let war 'spill over'

Meanwhile, China urged Russia and Ukraine not to let effects of their war "spill over" and called for a diplomatic resolution.

Chinese Foreign Minister Wang Yi also sounded a fresh warning on Taiwan amid tensions in the Taiwan Strait, saying Beijing would take "forceful steps" to prevent any outside support for the island's independence.

Chinese Foreign Minister Wang Yi called for 'fair and pragmatic' peace talks

Addressing the UN General Assembly, China's top diplomat stopped short of robustly supporting the invasion of Ukraine by Russia, nominally an ally of Beijing.

"We call on all parties concerned to keep the crisis from spilling over and to protect the legitimate rights and interests of developing countries," Mr Wang said.

He called for "fair and pragmatic" peace talks to resolve all global issues.

"China supports all efforts conducive to the peaceful resolution of the Ukraine crisis. The pressing priority is to facilitate talks for peace," Mr Wang said.

"The fundamental solution is to address the legitimate security concerns of all parties and build a balanced, effective and sustainable security architecture."

During his visit to the UN, Mr Wang met with Ukrainian Foreign Minister Dmytro Kuleba, in their first talks since Russia invaded its neighbor on 24 February.

Earlier this month, Russian President Vladimir Putin acknowledged Chinese "concerns" about Ukraine during a meeting with his counterpart Xi Jinping.

Before the war, Mr Putin had visited Beijing and the two nations declared a tight alliance.

But US officials have been heartened by what they see as China's lack of concrete backing for the war and say that Beijing has declined requests to send military equipment, forcing Russia to rely on North Korea and Iran as its own supplies dwindle.

China's reaction to Russia is being closely watched for clues on its approach to Taiwan, a self-governing democracy that Beijing claims as its territory.

Mr Wang met with US Secretary of State Antony Blinken and warned about efforts to back Taiwan, amid a push in the US Congress to supply direct military assistance to the island.

Addressing the General Assembly, where only Beijing and not Taipei has a seat, Mr Wang took a firm line in insisting on "reunification" with Taiwan.

"We must combat Taiwan independence separatist activities with the firmest resolve and take the most forceful steps to oppose external interference," Wang said.

"Any move to obstruct China's reunification is bound to be crushed by the wheels of history," he added.

Beijing says Taiwan was historically part of China and the mainland's defeated nationalists fled to Taipei after losing the civil war in 1949.

But Taiwan administers itself and many Taiwanese do not see a connection with China, although the Taipei leadership has stopped short of formally declaring independence.