Russian President Vladimir Putin today condemned Britain’s plans to send tank munitions containing non-enriched uranium and warned Moscow would “retaliate” if London supplies Ukraine with the munitions, reacting to comments by a British official.

“Today, we learned that the United Kingdom (…) had announced not only the delivery of tanks to Ukraine but also shells containing non-enriched uranium (…) If this happens, Russia will be forced to respond,” said Putin.

Meanwhile, Russian Defense Minister Sergei Shoigu said Britain’s decision leaves fewer and fewer steps before a possible “nuclear conflict” between Russia and the West, the Interfax news agency reported.

Shoigu’s statement was in response to reports that Britain will supply Ukraine with munitions containing non-enriched uranium, a move Moscow will respond to, according to Interfax.

Shoigu also said that “every war ends in peace,” Russia’s RIA news agency reported.

Speaking in London on Monday, Undersecretary for Defense Annabel Goldie said some of the ammunition for Challenger 2 tanks that Britain is sending to Ukraine includes projectiles containing unenriched uranium.

“If all this happens, Russia will have to respond accordingly, as the West collectively is already starting to use weapons with a nuclear component,” Putin said in remarks after a summit with Chinese President Xi Jinping, without elaborating.

“Another step has been taken and there are fewer and fewer left,” Shoigu told reporters in statements cited by domestic agencies.

“Of course, Russia has something to answer for this,” Shoigu told reporters when asked about the munitions.

Unenriched uranium is used in weapons because it can penetrate tanks and armor more easily due to its density and other physical properties, Goldie pointed out.

It is especially hazardous to health around the collision points, as dust can enter people’s lungs and other vital organs.

Earlier, Russian Foreign Ministry spokeswoman Maria Zakharova called the plan a Yugoslavia-style scenario, stressing that the munitions caused cancer and polluted the environment.