President Volodymyr Zelensky has said at least 155 Chinese were fighting with the Russian army -- two of whom have been detained by Ukraine -- and that he had "information" that China was supplying arms to Russia. China last week denied providing weapons.

The foreign ministry summoned China's envoy in Kyiv, Ma Shengkun, over the accusations and produced "evidence" to back the claims, the ministry said.

"Deputy Foreign Minister Yevhen Perebyinis stressed that the participation of Chinese citizens in hostilities against Ukraine on the side of the aggressor state, as well as the involvement of Chinese companies in the production of military products in Russia, are of serious concern and contradict the spirit of partnership between Ukraine and China," said a ministry statement.

"Evidence of these facts was passed by the Ukrainian special services to the Chinese side," it added.

"Perebyinis called on the Chinese side to take measures to stop supporting Russia in its aggression against Ukraine, which Beijing has repeatedly stated is not the case," said the ministry.

"Perebyinis assured that our country values its strategic partnership with China and expects that China will refrain from taking any steps that could harm bilateral relations in the future."

Beijing on Friday denied giving weapons to any party in three-year-old war.

"The Chinese side has never provided lethal weapons to any party in the conflict, and strictly controls dual-use items," foreign ministry spokesman Lin Jian said.

Earlier it said there was a lot of "manipulation and hype" surrounding two Chinese nationals captured in Ukraine. The two Chinese told a press conference in Kyiv that they hoped to be exchanged in a prisoner swap.