By Olena Harmash

KYIV (Reuters) -President Volodymyr Zelenskiy said on Wednesday that Ukrainian intelligence had information about 155 Chinese citizens fighting for the Russian military against Ukraine.

The Ukrainian leader was speaking to reporters after the capture of two Chinese nationals in eastern Ukraine, where Russian troops have been advancing. He said he hoped the United States would speak to Moscow about the battlefield deployment of Chinese citizens.

Zelenskiy said Russia was recruiting Chinese citizens via social media, that Chinese officials were aware of it and that Ukraine's security service had compiled lists of names, birth dates and the Russian military units where they were assigned.

Ukraine was trying to assess whether the recruits were receiving instructions from Beijing, he said.

"The Chinese issue is serious," Zelenskiy said. "There are 155 people with names and passport details - 155 Chinese citizens who are fighting against Ukrainians on the territory of Ukraine. We are collecting information and believe that there are more, many more."

Zelenskiy said Ukraine was prepared to exchange the captured Chinese nationals for Ukrainian servicemen now in detention.

Reuters could not independently verify the claims.

China, which has declared a "no-limits" partnership with Russia, has tried to position itself as an actor in attempts to negotiate an end to the war. It has refrained from criticising Russia's 2022 full-scale invasion of Ukraine.

On Wednesday, China's Foreign Ministry dismissed as "groundless" Zelenskiy's remarks that more Chinese nationals were on the front line alongside Russians.

"Ukraine should correctly view China's efforts and constructive role in seeking a political solution to the Ukrainian crisis," ministry spokesperson Lin Jian told a regular news conference.

China was verifying the situation with Ukraine, he said, adding that its government had always required its citizens to avoid areas of armed conflict and "especially to avoid participating in the military operations of any party."

NORTH KOREANS, CHINESE

Zelenskiy decried the deployment of Chinese nationals as Russia's "second mistake" in the war, after what Ukraine and Western countries have described as the dispatch of more than 11,000 North Korean troops to Russia's Kursk region.

"America is clearly seeing today the actions undertaken by Russia," he said. "I do not understand why America is not reacting forcefully towards Russia. There is nothing in terms of diplomacy or statements."

Russia has made no public comment on Zelenskiy's statements about Chinese fighters and has never explicitly confirmed deploying North Korean troops in its Kursk region.

The head of U.S. forces in the Indo-Pacific, Admiral Samuel Paparo, confirmed at a congressional hearing on Wednesday that Ukraine had captured two Chinese nationals and said any Russian success offensively in Europe would embolden China in its own offensive ambitions.

In other comments, Zelenskiy said he believed U.S. President Donald Trump was irritated by the Kremlin's failure to make good on pledges, referring to Russia's rejection of a U.S. proposal last month to declare a full-fledged ceasefire and continuing strikes on Ukrainian targets.

"I believe Trump is annoyed that (Russian President Vladimir) Putin is not following through on what he promised," Zelenskiy said. "We don't know everything they talked about, but we know a lot. And we really expect there to be a reaction."

Zelenskiy also said a meeting scheduled for this week in the United States to discuss a deal on exploiting minerals and rare earths would focus on technical aspects and foundations of a future agreement.

Zelenskiy said the deal should be profitable for both sides and could be structured in a way to help modernize Ukraine.

(Reporting by Olena Harmash;Editing by Alison Williams, Ron Popeski and Rod Nickel)