Rounds of Chinese ammunition have been used in the battlefields in Ukraine and are suspected to have been fired by Russian forces, said sources from the United States government on Friday.

According to a report by Kyodo News on Saturday, the sources said it was unclear whether the ammunition was supplied by China, but an analysis by the US government of the ammunition’s composition confirmed its Chinese origin.

The type of ammunition found was not disclosed. The sources added that Washington is ready to take action if the shipments are verified to have been made by China.

US officials have been claiming that Beijing is contemplating sending lethal aid, including ammunition and artillery, to Russia for the war in Ukraine, though this has been strongly denied by Beijing.

“It’s something that we are vigilant about and continuing to watch carefully,” a US State Department official told Kyodo News.

News of Chinese ammunition being used in the battlefields of Ukraine comes as China’s President Xi Jinping is expected to travel to Moscow for a three-day state visit from Monday.

It will be Mr Xi’s first trip to Russia since its invasion of Ukraine began in February 2022. It will also be the Chinese leader’s first overseas trip after winning his third presidential term earlier in March.

Without mentioning the war in Ukraine, Chinese Foreign Ministry spokesman Wang Wenbin said the objective of the visit is to further deepen bilateral trust between both countries and promote “peace”.

A Russian official said the two leaders would discuss the conflict in Ukraine and “military-technical cooperation”.

China, Russia’s most important ally, increased its imports of Russian liquefied natural gas and oil as other countries stopped buying Russian energy products to punish it for the war.

A report by US news website Politico claimed that Chinese companies, including one connected to the Chinese government, have sent Russia 1,000 assault rifles and other military equipment such as drone parts and body armour.

The shipments took place between June and December 2022, according to trade and Customs data obtained by Politico.

The report added that data did not show whether the items were sent to Russia specifically to aid war efforts in Ukraine.