German President Frank-Walter Steinmeier on Friday questioned China's willingness to mediate in the conflict between Ukraine and Russia, after Beijing called for urgent peace talks to end the war.

"Every constructive suggestion that brings us closer on the path to a just peace is highly welcome," Steinmeier said on the anniversary of Moscow's invasion of Ukraine.

"Whether global power China wants to play such a constructive role is still doubtful," he said.

China on Friday published a 12-point paper on the "political settlement" of the war in Ukraine, calling on the two sides to come to the negotiating table.

Top Chinese diplomat Wang Yi met on Wednesday with Russia's foreign minister Sergei Lavrov and President Vladimir Putin in Moscow.

Following Wang's visit, Moscow said Beijing had presented its views on approaches to a resolution of the conflict.

Ukrainian President Volodymyr Zelensky said Thursday he had not seen any Chinese peace plan and wanted to meet with Beijing over the proposal before assessing it.

If China did want to play a constructive role it should "not just speak with Moscow, but also with Kyiv", Steinmeier said.

China should also "join the overwhelming majority of states and work for peace under the umbrella of the United Nations", Steinmeier added.

Beijing on Thursday abstained in a nonbinding UN vote to demand Russia immediately and unconditionally withdraw its troops from Ukraine.