Kyiv says Chinese citizens are now fighting for the Russians in Ukraine, adding a new dimension to a conflict that shows no sign of soon ending.

The entry of the Chinese into the war, disavowed by Beijing, surged into the calculations of what the Ukrainians are up against when two of them were captured by Ukrainian troops in the bitterly contested Donetsk region, southeast of the Ukrainian capital of Kyiv. As described by President Zelensky, the prisoners were carrying passports and credit cards showing they were “citizens of China” — a sign that Beijing is departing from its policy of avoiding direct involvement in the war while making a show of searching for peace.

The fear is that many more Chinese will “volunteer” to fight in Ukraine, joining Russian units as the North Koreans have been doing since 11,000 of them arrived six months ago. One great difference, though, is that the North Koreans are fighting inside Russia, suffering heavy casualties as they battle Ukrainians who had crossed into Russia’s Kursk region, whereas the Chinese were captured on the Ukrainian side of the border.

Mr. Zelensky, anxious to drum up support among EU leaders for a European peace-keeping force capable of providing  security during a cease-fire, said “significantly more Chinese citizens” were in Russian units, according to the Kyiv Post. He showed a video of a man speaking in Chinese but identified as a Korean soldier, all of whom are ostensibly in Russian units.

The magazine Kviv Independent cited a Ukrainian intelligence document saying “at least 163 Chinese nationals” were serving in Russia’s armed forces as of early April. Another document, it said, “showed photos and passport details of 13 Chinese recruits who were being selected for service in the Russian army as of April 2.” The magazine claimed to have seen the documents, including names, personal data, places of service, and positions in the Russian army along with “photos of some of them.”

The website Ukrainska Pravda quoted one of the Chinese soldiers as claiming he had paid 300,000 rubles — about $3,500 — to a middleman in China to join the Russian military in exchange for the promise of citizenship. “Beijing knows about this,” Mr. Zelensky reportedly said, because “Russians distribute advertising videos about recruitment through Chinese social networks.”

It was still not clear, though, if China had dispatched its own soldiers to fight in Ukraine or if the volunteers were mercenaries eager to escape repressive conditions in China, experience an exciting adventure, and then live in Russia. A Chinese spokesman at Beijing denied China was doing anything other than looking for a resolution to the conflict. Mr. Zelensky said he had asked his foreign and defense ministers to demand explanations from their opposite numbers in China.

While President Trump hopes to persuade President Putin to agree to a cease-fire, a Department of State spokeswoman, Tammy Bruce, called China “a major enabler in the war.” The Chinese, she said, were plying their Russian ally with vital parts and technology — not exactly “weapons” per se, but needed to make them.

Ukraine dramatized its report of Chinese in Ukraine with a video of a Chinese prisoner describing a Ukrainian drone attack in which both he and his commander were wounded. “Vroom vroom … boom boom boom boom boom … and then my commander … ‘Boom,” were his words as interpreted in the Kyiv Post, as he “mimicked the explosions and subsequent injuries for both him and his commander.”

Mr. Zelensky clearly had two audiences in mind in publicizing the capture of the Chinese soldiers. Among NATO leaders, he wanted to make certain of their commitment to maintaining a steady flow of arms and ammunition despite his clash with Mr. Trump on the terms of a truce, which he insists must include “guarantees” to be meaningful.

Second, of course, he’s hoping Mr. Trump will come to share his view “that the U.S. would strengthen its cooperation with Ukraine in light of the situation, and engage in dialogue with Russia.”