United States President Joe Biden and Chinese President Xi Jinping will hold their first direct talks since November later on Friday, amid growing US concern over Beijing’s relationship with Russia and its stance on the increasingly brutal war in Ukraine.

Biden and Xi will speak on the phone at 13:00 GMT on Friday, the White House said, amid warnings from Washington that China may be considering providing military support to Russia.

In a briefing earlier, US Secretary of State Antony Blinken said that Biden would use the call to “make clear that China will bear responsibility for any actions it takes to support Russia’s aggression”, and there would be “costs” to such actions.

China “in particular has a responsibility to use its influence with President Putin and to defend the international rules and principles that it professes to support,” he said.

While Western countries and allies have moved to impose tough sanctions on Russia over the invasion and condemned its aggression, China, which has a close relationship with Kyiv as well as with Moscow, has not.

Walking a diplomatic tightrope, it has stressed Ukraine’s sovereignty while strenuously avoiding any direct criticism of Russia and calling for peace negotiations.

It has also insisted that Russia has legitimate security concerns that need to be addressed and echoed Russian claims the US has been secretly working on biological weapons in Ukraine. The allegations have been rejected by the US and the United Nations.

“Since the beginning of the invasion, China has tried, I think, very awkwardly, to try and play a neutral role,” said Katrina Yu, Al Jazeera’s correspondent in Bejing.

“It’s refused to take sides, saying that it’s got good relations with both Kyiv and Moscow.

“It says that it’s a neutral player and just wants to encourage dialogue. But at the same time, Beijing has made it very clear that it intends to preserve its friendship with Russia, which it has called ‘limitless’ [and] ‘rock solid’.”

At a regular briefing of China’s Ministry of Foreign Affairs on Thursday, spokesperson Zhao Lijian insisted China’s position was consistent and rounded on those who suggested any incongruity.

“It is those countries that delude themselves into thinking that they can lord it over the world after winning the Cold War, those that keep driving NATO’s eastward expansion five times in disregard of other countries’ security concerns, and those that wage wars across the globe while accusing other countries of being belligerent, that should really feel “uncomfortable”,” he told reporters.

Xi and Putin have met more than 30 times since 2013, most recently in Beijing last month where Putin was a guest at the opening ceremony of the Winter Olympic games.

China and Russia have grown increasingly close in recent years, although Beijing has never recognised Russia’s claim over Crimea, which Moscow annexed in 2014.

Putin, who appears to have developed a close bond with Xi, was in Beijing shortly before the invasion for the opening of the Winter Olympic Games. The two men have met more than 30 times since 2013.

The call between Xi and Biden comes after a marathon meeting on Monday between Yang Jiechi, director of China’s central foreign affairs commission, and US National Security Adviser Jake Sullivan in Rome.

China said those talks were “frank, in-depth and constructive” and included discussion on Taiwan.

Yu says the self-ruled island, which China claims as its own, was also likely to be on the agenda of the Biden-Xi call.

Beijing was furious after former Secretary of State Mike Pompeo visited Taiwan earlier this month and said the US should recognise it as a “free and sovereign” nation.

The US, which maintains formal diplomatic relations with Beijing, has a policy of “strategic ambiguity” on Taiwan.

Under 1979’s Taiwan Relations Act, the US government is mandated to “preserve and promote extensive, close and friendly commercial, cultural, and other relations between the people of the United States and the people of Taiwan”.

In recent years, amid concerns about the threat posed by Beijing, it has also stepped up arms sales to the island.

-Aljazeera