Ukraine has expanded on its claim that significant numbers of Chinese nationals are fighting for Russia's invading army, saying it had gathered detailed intelligence on more than 150 mercenaries Moscow allegedly recruited through social media.
In China, officials called the allegations "totally unfounded."
The Ukrainian accusation and Chinese denial come as the US strives to secure a ceasefire in the more than three-year war.
President Volodymyr Zelenskyy announced on Tuesday that the Ukrainian military had captured two Chinese men fighting alongside the Russian army on Ukrainian soil. It was the first time Ukraine had made such a claim about Chinese fighters in the war.
On Wednesday, Zelenskyy said he was willing to exchange the two prisoners of war for Ukrainian soldiers held captive in Russia. Without providing evidence, Zelenskyy said officials in Beijing were aware of Russia's campaign to recruit Chinese mercenaries. He stopped short of saying the Chinese government authorised the mercenaries' involvement in Ukraine.
Zelenskyy said Ukraine has the last names and passport data for 155 Chinese citizens fighting for the Russian army and that "we believe that there are many more of them."
He shared with journalists documents listing names, passport numbers and personal details of the alleged Chinese recruits, including when they arrived in Russia for military training and departed for service; the AP has not independently verified the documents.
China has provided strong diplomatic support for Russia since it launched its full-scale invasion of Ukraine in February 2022. It has also sold Russia machinery and microelectronics that it can use to make weapons, Western officials say, in addition to providing an economic lifeline through the trade in energy and consumer goods.
China is not believed to have knowingly provided Russia with troops, weapons or military expertise.
US officials have accused Iran of providing Russia with drones, while American and South Korean officials say North Korea has sent thousands of troops and ammunition to help Russia on the battlefield.
With the US and Europe having provided substantial military support and diplomatic heft for Ukraine, the war has to some degree become a contest between power blocs.
Tensions between the US and China have deepened in recent years. Disputes have centered on geopolitical influence, technology and trade — and recently escalating import tariffs between the countries have roiled global financial markets. Zelenskyy said US officials expressed "surprise" when informed of the presence of Chinese mercenaries in Ukraine.
US President Donald Trump is trying to follow through on a campaign promise last year to swiftly end the war in Ukraine.
