As invasion of Ukraine continues, U.S. warns China against helping Russia evade sanctions

The U.S. and China are sending top aides to Rome on Monday as tensions between the two countries mount over the Russia-Ukraine war and worries spread that the conflict will take even darker turns.

In advance of the talks, White House national security adviser Jake Sullivan bluntly warned China to avoid helping Russia evade punishment from global sanctions that have hammered the Russian economy. "We will not allow that to go forward," he said.

U.S. officials are also accusing China of spreading Russian disinformation that could be a pretext for chemical or biological weapons attacks launched by Vladimir Putin's forces in Ukraine.

Russia's invasion of Ukraine has put China in a delicate spot with two of its biggest trading partners: the U.S. and European Union. China needs access to those markets, yet it also has made gestures supportive of Moscow, joining with Russia in declaring a friendship with "no limits."

In his talks with senior Chinese foreign policy adviser Yang Jiechi, Sullivan will indeed be looking for limits in what Beijing will do for Moscow.

"I'm not going to sit here publicly and brandish threats," he told CNN in a round of Sunday news show interviews. "But what I will tell you is we are communicating directly and privately to Beijing that there absolutely will be consequences" if China helps Russia 'backfill' its losses from the sanctions.

"We will not allow that to go forward and allow there to be a lifeline to Russia from these economic sanctions from any country anywhere in the world."

The White House said the talks will focus on the direct impact of Russia's war against Ukraine on regional and global security.

Biden administration officials say Beijing is spreading false Russian claims that Ukraine was running chemical and biological weapons labs with U.S. support. They say China is effectively providing cover if Russia moves ahead with a biological or chemical weapons attack on Ukrainians.

When Russia starts accusing other countries of preparing to launch biological or chemical attacks, Sullivan told NBC's Meet the Press, "it's a good tell that they may be on the cusp of doing it themselves."

Pentagon spokesperson John Kirby, on ABC's This Week, said "we haven't seen anything that indicates some sort of imminent chemical or biological attack right now, but we're watching this very, very closely."

The striking U.S. accusations about Russian disinformation and Chinese complicity came after Russian Foreign Ministry spokesperson Maria Zakharova alleged with no evidence that the U.S. was financing Ukrainian chemical and biological weapons labs.

The Russian claim was echoed by Chinese foreign ministry spokesperson  Zhao Lijian, who claimed there were 26 bio-labs and related facilities in "which the U.S. Department of Defense has absolute control." The United Nations has said it has received no information backing up such accusations.

White House press secretary Jen Psaki called the claims "preposterous."