Russian President Vladimir Putin has warned that Moscow will "have to respond" if Britain supplies Ukraine with ammunition and other weapons containing uranium.
Putin spoke after hearing the statement of the British Minister of Defense, Annabel Goldie, that the ammunition containing uranium is part of the military aid sent to Ukraine along with the Challenger 2 battle tanks.
"Britain announced not only the supply of tanks to Ukraine but also missiles with depleted uranium.
If this happens, Russia will have to take action," Putin told reporters after talks with Chinese leader Xi Jinping at the Kremlin.
"If all this happens, Russia will have to respond accordingly, given that the West has already started using nuclear weapons."
Responding to questions about the ammunition, Minister Goldie said on Monday that "along with our supply of Challenger 2 tanks to Ukraine, we will be supplying ammunition including armor-piercing rounds that contain depleted uranium".
The bullets "were very effective in defeating modern tanks and armored vehicles", he said.
Depleted uranium is a product of the nuclear enrichment process used to make nuclear fuel or nuclear weapons.
Its weight can be used in armor piercing rounds as it helps them penetrate metal easily.
The United Nations Environment Program has described the bullets as "heavy metal with chemical and radiological toxicity".