Russian Deputy Foreign Minister Sergei Ryabkov said on Thursday that the US supply of depleted uranium weapons to Ukraine was "a criminal act," state media reported.
The Pentagon on Wednesday announced a new security assistance package worth up to $175 million for Ukraine, including depleted uranium ammunition for US Abrams tanks.
A by-product of uranium enrichment, depleted uranium is used for ammunition because its extreme density gives rounds the ability to easily penetrate armor plating. Critics say there are dangerous health risks from ingesting or inhaling depleted uranium dust, including cancers and birth defects.
"This is not just an escalatory step, but it is a reflection of Washington’s outrageous disregard for the environmental consequences of using this kind of ammunition in a combat zone. This is, in fact, a criminal act, I cannot give any other assessment," TASS quoted Ryabkov as saying.
In a speech at a security seminar, he also reiterated previous warnings by Russia about the risk of a nuclear war, because of what he called Western "pressure" on Moscow.
Nuclear deterrence
"Now this pressure is dangerously balancing on the brink of direct armed conflict between nuclear powers," he said.
Russia has long accused the West of using Ukraine to wage a proxy war aimed at inflicting a "strategic defeat" on Moscow. The United States and its allies say they are arming Ukraine to defend itself against Russia's invasion and recover territory seized by Moscow in the course of the 18-month war.
Russia's deployment of tactical nuclear weapons in Belarus was proceeding on schedule, Ryabkov said.
"Several stages have now been completed in terms of creating the appropriate infrastructure and re-equipping the corresponding carriers. This work continues."
Moscow announced the deployment earlier this year, calling it a deterrent to the West.