Ukraine's President Volodymyr Zelenskyy said he has had a "long and meaningful" call with Chinese President Xi Jinping.
During the long-anticipated conversation between the two leaders, Xi appealed for Russia and Ukraine to restart peace talks and warned "there is no winner in a nuclear war", according to state media.
The Chinese government pledged to send a "special representative" to Kyiv for talks about a possible "political settlement".
Writing on Twitter following the discussion, Mr Zelenskyy said: "I had a long and meaningful phone call with... President Xi Jinping.
"I believe that this call, as well as the appointment of Ukraine's ambassador to China, will give a powerful impetus to the development of our bilateral relations."
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It comes two months after Beijing said it wanted to act as a peace mediator.
China has tried to appear neutral about the conflict, but has refused to condemn Moscow's invasion of Ukraine.
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President Xi reportedly said China will send special representatives to Ukraine to hold talks with "all parties" on the "political settlement of the Ukrainian crisis".
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He said China is willing to continue to provide "humanitarian assistance" to Ukraine.
"The two sides should focus on the future, persist in viewing and planning bilateral relations from a long-term perspective, continue the tradition of mutual respect and sincerity between the two sides," he said.
'No winner in a nuclear war'
"Negotiation is the only viable way out," Chinese state TV also quoted Xi as saying in a report about the call.
He added: "There is no winner in a nuclear war.
"All parties concerned should remain calm and restrained in dealing with the nuclear issue and truly look at the future and destiny of themselves and humanity as a whole and work together to manage the crisis."
Before the February 2022 invasion, the Chinese president and Russian President Vladimir Putin issued a joint statement saying their governments had a "no limits friendship".
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But earlier this year, the Chinese government released a peace proposal and called for a ceasefire and talks.
The phone call between the two leaders was for China another step toward deeper involvement in resolving the ongoing war.
It comes after Mr Zelenskyy said in late March that he had not spoken with Xi since the war began before extending an invitation for him to visit Ukraine.
Why China's stance matters
An official for China's foreign ministry added that President Xi's call with President Zelenskyy "shows China's objective, impartial position on international affairs".
They said what the country has done to help resolve the crisis has been "above board".
Sky's Asia correspondent Helen-Ann Smith said the phone call between President Zelenskyy and President Xi is "really significant," adding: "China's position on this war is really very important, it is presenting itself as a potential peacemaker."
She added: "It wants to be seen as the power capable of brokering peace because it says it is one of the only mutual parties.
"The West sees that claim with a degree of scepticism. China has never condemned the invasion, but it has provided Russia with finance and technology and significant diplomatic cover."

This data comes from MediaIntel.Asia's Media Intelligence and Media Monitoring Platform.