The US Department of Defense said on Sunday that there are no signs of any "inevitable chemical or biological attack by Russia in Ukraine."

“Well, I want to be careful. We don't get into intelligence assessments here. We continue to watch this very, very closely. It is of the Russian playbook … they accuse you of [what] they're planning to do now. Again, we haven't seen anything to indicate some sort of imminent chemical, chemical biological attack right now, but we're watching this very, very closely,” US Defense Department Spokesperson John Kirby told the ABC broadcaster.

NATO chief Jens Stoltenberg claimed this weekend that Russia could be planning a chemical operation, although the Russian troops were the ones who exposed US-linked secret biological labs in Ukraine to the world.

Earlier, the United States was concerned the bioweapons could come under the control of the Russian forces, Under Secretary of State for Political Affairs Victoria Nuland said.

"Ukraine has biological research facilities, which, in fact, we are now quite concerned Russian forces may be seeking to gain control of," Nuland said during a Senate hearing.

According to the Under Secretary, Washington is working with Kiev on how they can prevent any of those research materials from falling into the hands of Russian forces "should they approach."

Igor Kirillov, the head of the radiation, chemical, and biological defense of the Russian armed forces, reported that Russian forces found 30 biological laboratories in Ukraine, possibly used to develop biological weapons.

"The Russian Defense Ministry has repeatedly drawn attention to the military biological programs that are being implemented by the Pentagon in post-Soviet countries, including on the territory of Ukraine, where a network of more than 30 biological laboratories has been formed, which can be divided into research and sanitary-epidemiological ones," Kirillov said.

It is worth emphasizing that the US is keeping a close eye on the situation in Ukraine after the biolabs were discovered, even though it reportedly denied any involvement in them. That can only indicate one thing, the US' role in the labs and its fear of more information being disclosed. 

It's worth mentioning that on February 24, Russian President Vladimir Putin launched a special military operation in Ukraine following a request for assistance from Donbass' leaders.