US President Joe Biden has warned Chinese leader Xi Jinping there will be "consequences" if Beijing gives material support to Russia's invasion of Ukraine, as both sides stress the need for a diplomatic solution to the crisis.
Meanwhile, Russia has pledged its ties with Beijing will only get stronger in the face of Western pressure.
In a video call that lasted just under two hours at a time of deepening acrimony between the world's two biggest powers, Biden detailed efforts of the United States and its allies to respond to the invasion, including by imposing costs on Russia.
"He described the implications and consequences if China provides material support to Russia as it conducts brutal attacks against Ukrainian cities and civilians," the White House said on Friday, adding that Biden "underscored his support for a diplomatic resolution to the crisis".
China's foreign ministry said Xi told Biden the war in Ukraine must end as soon as possible and called on NATO nations to enter dialogue with Moscow.
"The top priorities now are to continue dialogue and negotiations, avoid civilian casualties, prevent a humanitarian crisis, cease fighting and end the war as soon as possible," Xi said.
He said all parties should support Russia-Ukraine negotiations, while Washington and NATO should also conduct talks with Russia to solve the "crux" of the Ukraine crisis and resolve security concerns.
"The Ukraine crisis is something that we don't want to see," Chinese state media quoted Xi saying in the call, which it said was requested by the US side.
Later in the day, Russia's Interfax news agency quoted Foreign Minister Sergei Lavrov as saying Moscow's links with China would only become stronger.
"This co-operation will get stronger, because at a time when the West is blatantly undermining all the foundations on which the international system is based, of course we - as two great powers - need to think how to carry on in this world," Lavrov was quoted as saying.
On Thursday, US Secretary of State Antony Blinken said the Biden administration was concerned China was considering directly assisting Russia with military equipment for use in Ukraine, something Beijing has denied.
Washington is also worried China could help Russia circumvent Western economic sanctions.
Ukraine has added a new front in a US-Chinese relationship already at its worst level in decades.
Biden has been anxious to avoid a new "Cold War" with China but China's "no-limits" strategic partnership with Russia announced last month and its stance on Ukraine has called that into question.
Before the call, a Chinese aircraft carrier sailed through the sensitive Taiwan Strait on Friday. it was shadowed by USS Ralph Johnson, an Arleigh Burke guided missile destroyer.
China claims Taiwan as its own and has stepped up its military activity near the islands, alarming Taipei and Washington amid concerns Beijing might follow Russia's example and use force.
China has refused to condemn Russia's action in Ukraine or call it an invasion.
While saying it recognises Ukraine's sovereignty, Beijing has said Russia has legitimate security concerns that should be addressed and urged a diplomatic solution to the conflict.
Australian Associated Press
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