Fears grow over Russian chemical threat to Ukraine

Biden administration officials are raising alarms about the threat that Russia will escalate its war on Ukraine with chemical weapons, but are stopping short of establishing red lines that would involve U.S. military intervention.

Officials have raised the prospect that Russia is laying the foundation for a chemical or biological attack on Ukraine, and experts and world leaders have openly discussed the risk of escalation given Russia's nuclear arsenal.

"I'm not going to get into hypotheticals," White House press secretary Jen Psaki said at a Thursday briefing when asked what the U.S. might do in response to such escalation.

"What we're saying right now is they have the capacity and capability [for a chemical weapons attack]. I'm also not going to get into intelligence. But the president's intention of sending U.S. military into Ukraine against Russia has not changed," she said.

The White House has been adamant and consistent for weeks that Biden would not authorize putting U.S. troops on the ground in Ukraine to fight Russia, arguing it would risk drawing the country into a protracted and potentially global war.

Psaki on Thursday avoided laying out a "red line" Russia could cross for Biden to reconsider how the U.S. might increase or alter its involvement. The move may have been deliberate given the criticism faced by former President Obama over his failure to enforce his so-called red line on the use of chemical weapons on civilians in Syria.

The U.S. and its allies have put stiff economic sanctions on Moscow that the Kremlin has described as an act of war. Such sanctions have yet to deter Russia, though they are clearly causing some pain.

Multiple administration officials on Wednesday cited Russian allegations that the United States was developing bioweapons in Ukraine - which they dismissed as "false" and "laughable" - as a possible pretext for Moscow to deploy chemical weapons of its own in Ukraine.

"I think it underscores the concern that all of us need to focus on those kind of issues, where it's the potential for a use of chemical weapons either as a false flag operation, or as against Ukrainians," CIA Director William Burns told lawmakers on Thursday.

"This is something ... very much a part of Russia's playbook. They've used those weapons against their own citizens; they've at least encouraged the use in Syria and elsewhere. So it's something we take very seriously."

And a senior defense official told reporters Thursday the U.S. has picked up intelligence that Russians could be making the false claims about U.S. and Ukrainian work in biodefense as a pretext to use chemical agents in an attack.

"We have indications that this public narrative of theirs could be setting the conditions for a false flag event of some kind ... that could be the actual use of some sort of agents that they would blame on the Ukrainians and by association, perhaps even the United States, to create, again, an excuse for potentially more aggressive military action or some other way of advancing their military interest in Ukraine," they said.

The biolabs at the center of Russia's propaganda push are, in fact, used for research to help address pandemics or the spreading of pathogens and other health concerns, Director of National Intelligence Avril Haines told the Senate committee.

She said Ukraine operates a little over a dozen such labs and that the U.S. government has, at least in the past, provided assistance to them "in the context of biosafety," something it's done with a variety of different countries.

"Let me be clear: We do not assess that Ukraine is pursuing either biological weapons or nuclear weapons, which have been basically the propaganda that Russia is putting out," said Haines.

Despite the threat of Russia amping up the conflict, the U.S. has been reluctant to take actions that could be viewed by the Kremlin as escalatory, wary of anything that might prompt more violent attacks on Ukraine or spill over into NATO countries and draw others into a global conflict.

Russia's nuclear capabilities have further complicated that matter, as U.S. officials have ruled out establishing a no-fly zone over Ukraine that would mean shooting down Russian planes and have nixed transferring fighter jets from Poland to Ukraine.

Haines told senators on Thursday that the intelligence community is closely monitoring any changes in Russia's strategic nuclear posture but so far had not seen any significant changes, amid concerns Putin may introduce these weapons onto the battlefield.

"It's nothing unprecedented," she said of Russia's strategic nuclear posture.

But Putin's unpredictability has still left some experts concerned.

"You never know what someone like Putin, when you back him to the wall - he's a tyrant. He's a dictator, clearly doesn't care about human rights and humanitarian issues," John Kelly, a retired four-star general and former chief of staff to then-President Trump, said on CNN. "You back a guy like that against the wall and leave him no out, I think he will go down swinging. And that would include, very possibly, the use of tactical nuclear weapons."

What's more, "the world is aware of Russia's willingness to use chemical agents" and nerve agents, even against their own citizens, including in the attempted assassination of former Russian military intelligence officer Sergei Skripal in the United Kingdom in 2018, a senior defense intelligence official told reporters Thursday.

They also pointed to the 2002 Moscow theater hostage crisis, when nearly 1,000 people became trapped after the Dubrovka Theater was seized by a group of Chechen terrorists. Russian law enforcement pumped a chemical agent into the building's ventilation system to break up the attack but killed up to 130 hostages in the process.

Though neither example is related to a military conflict, they underscore the Kremlin's inclination to use a heavier hand when faced with resistance. With Russia's grinding attack on Ukraine now entering its third week, officials are worried Moscow may resort to more barbaric tactics to gain a win, including using chemical weapons.

"It is time for the world to realize that Putin, as he is losing to the Ukrainian army, is ready to use his chemical and biological weapons," Borislay Bereza, a former member of Ukrainian parliament and member of the Ukrainian delegation in Parliamentary Assembly of the Council of Europe (PACE), said in a statement.

Laura Kelly contributed.