White House Press Secretary Jen Psaki on Thursday warned against Russia's possible use of chemical or biological weapons in Ukraine, adding "we should all be on the lookout".
Psaki's remark came after Russia's Embassy in the UK referred to claims that "recently found documents" showed components of biological weapons were made in Ukrainian laboratories - with funding from the US Department of Defense.
In response, the Press Secretary tweeted: "Now that Russia has made these false claims, and China has seemingly endorsed this propaganda, we should all be on the lookout for Russia to possibly use chemical or biological weapons in Ukraine, or to create a false flag operation using them. It's a clear pattern."
She called the allegation "preposterous" and that it is the "kind of disinformation operation we've seen repeatedly from the Russians over the years in Ukraine and in other countries, which have been debunked".
Psaki went on to say that the US was in full compliance with its obligations under the Chemical Weapons Convention and the Biological Weapons Convention and "does not develop or possess such weapons anywhere".
She further accused Russia of having a "long and well-documented track record of using chemical weapons, including in attempted assassinations and poisoning of (Russian President Vladimir) Putin's political enemies like Alexey Navalny".
The Press Secretary also said that Russia continues to support the Bashar al-Assad regime in Syria, "which has repeatedly used chemical weapons" against civilians.
"Russia has a track record of accusing the West of the very violations that Russia itself is perpetrating. In December, Russia falsely accused the U.S. of deploying contractors with chemical weapons in Ukraine.
"This is all an obvious ploy by Russia to try to try to justify its further premeditated, unprovoked, and unjustified attack on Ukraine," she added.
Chemical weapons are banned under international humanitarian law regardless of a valid military target because their effects are indiscriminate by nature and designed to cause superfluous injury and unnecessary suffering.
Psaki's remarks come as Russia's war on Ukraine continued for the 15th day on Thursday.
