There was no immediate comment from China. Beijing is not known to have provided Russia with weapons or military expertise, and it was not clear whether the Chinese had joined the fight on their own initiative. Russia allows foreigners to enlist in its military, as does Ukraine.

Zelenskyy said he asked his top diplomat “to immediately contact Beijing”. He said China would be the third country to offer military support to Russia after Iran, which has supplied attack drones, and North Korea, which has supplied soldiers, according to American and South Korean officials.

China has provided strong diplomatic support for Russia since Moscow launched its full-scale invasion of its neighbour in February 2022. Beijing has also offered an economic lifeline through the trade in energy and consumer goods.

Zelenskyy said a clash with Chinese soldiers occurred near the villages of Tarasivka and Bilohorivka in Donetsk, where six Chinese military personnel engaged Ukrainian troops. Two Chinese were taken prisoner, Zelenskyy said.

Ukraine’s Foreign Minister, Andrii Sybiha, said his ministry summoned China’s chargé d’affaires to demand an explanation, saying on X that “Chinese citizens fighting as part of Russia’s invasion army in Ukraine puts into question China’s declared stance for peace and undermines Beijing’s credibility as a responsible permanent member of the UN Security Council.”

Zelensky also posted footage on X showing what he said was one of two Chinese citizens captured by the Ukraine army.

Russia has effectively rejected a US proposal for an immediate and full 30-day halt in the fighting in Ukraine, and both sides are believed to be readying a spring-summer campaign on the battlefield.

“I cannot see any indications that would lead to a ceasefire or even a peace, but I see many indications (for) the continuation of the war,” Nico Lange, a senior fellow at the Center for European Policy Analysis in Washington, said in an analysis Monday.

Zelenskyy spoke at a news conference in Kyiv alongside visiting Belgian Prime Minister Bart De Wever, who announced a €1 billion ($1.85 billion) aid package for Ukraine this year. Ukraine’s president said they discussed joint military manufacturing efforts and Belgian private investment in Ukraine’s defence sector.

Meanwhile, Kremlin spokesperson Dmitry Peskov said Russian Foreign Ministry officials will take part in talks with the US in Istanbul planned for Thursday.

He didn’t say what the talks would be about, but the foreign ministry’s involvement suggests it is another round of talks about normalising their respective embassies’ operations and increasing staff numbers after years of expelling each other’s diplomats.

Russia reclaiming ground in Kursk region

Russian attacks on Ukraine in the last 24 hours killed at least three people and injured 19 others, according to Ukrainian officials. Russia carried out attacks on the Ukrainian regions of Dnipropetrovsk, Donetsk, Kharkiv and Kherson, local officials said.

Elsewhere on the frontlines, Russia’s Ministry of Defence said on Tuesday that it has retaken one of the last villages held by Ukraine in the Kursk region, months after Kyiv launched a surprise cross-border incursion.

“The Armed Forces of the Russian Federation continue to defeat the Ukrainian Armed Forces formations in the Kursk region. Units of the North group of forces have liberated the settlement of Guyevo in the Kursk region during offensive operations,” the Russian Ministry of Defence said in a statement.

The US-based conflict monitor the Institute for the Study of War (ISW) said in an update Monday that Russian forces have recently advanced in Kursk. ISW’s map of the incursion shows that Ukrainian troops remain only in small parts of the Russian region.

Ukrainian troops have occupied part of the Kursk region since August 2024, though Russian forces have since recaptured much of the territory.

Meanwhile, a Ukrainian regiment released video on Tuesday showing strikes on Russia’s neighbouring Belgorod region, one day after Zelensky confirmed for the first time on Monday that his country’s troops have been active in the region as they seek to protect Ukrainian towns near the border.

Ukraine’s 225th separate assault regiment said the video shows its forces destroying two bridges in Belgorod, in the villages of Grafovka and Nadezhevka. CNN has verified that those are the locations shown in the video.

“Then the drone operations and clearing the ground followed,” the regiment said in a Telegram post, confirming their presence on the ground in Russian territory.

Ukrainian forces began limited attacks in Russia’s northwestern Belgorod region on March 18, according to ISW, in areas just across the border from Ukraine. The Russian Defence Ministry previously said it defeated Ukrainian troops attacking Belgorod.