(NewsNation) — China maintained that it remains impartial in the Russian war on Ukraine, following reports that it responded positively to a Russian request for military supplies.

National security adviser Jake Sullivan on Tuesday held a tense seven-hour meeting with China, where the U.S. warned China not to help Russia despite it being one of the country’s key allies.

“It was a timely and important moment to have this conversation, especially given the reports we’ve seen,” press secretary Jen Psaki said.

Reports indicate that Russia has asked China for military equipment since the start of the invasion, an accusation the Chinese military spokesman called fake news.

Foreign Ministry spokesperson Zhao Lijian accused the U.S. of creating and spreading disinformation.

“This is not only unprofessional but also immoral and irresponsible,” he told reporters at a daily briefing. The Kremlin has also denied reports that it asked for Chinese military supplies.

Should China provide military or other assistance to Russia that violates sanctions or supports war efforts, the country will suffer significant consequences, Psaki said, adding that specifics of what those would look like would be coordinated with U.S. partners and allies.

“Whether that’s financial support to Russia, any such support from anywhere in the world would be of great concern to us,” Ned Price, spokesman for the State Department, said.

Senior U.S. officials say Sullivan was direct about the potential implications of helping Russia and reiterated the unprecedented coordination being seen now among the US and NATO allies, as well as the call President Joe Biden had been on shoring up solidarity with Indo-Pacific partners.

China called Tuesday’s talks constructive, saying that it remains impartial on Russia’s invasion of Ukraine. Beijing has refused to criticized Russia over its attacks, or refer to the conflict as a “war.”

Some have urged China to support Ukraine, such as the European Union ambassador to China, Nicolas Chapuis.

“There can be no so-called neutrality,” he said.

But John F. Tefft, a retired United States diplomat who served as a foreign service officer for more than 45 years, says neutrality is not what China should wants either.

“I don’t think they really want to get caught in the middle here,” Tefft said Tuesday night on “The Donlon Report”. “They don’t want to get sanctioned further by the U.S. or Europe and I think they want to be careful about getting drawn into some kind of deal with the Russians that would further jeopardize their own interests.”

Senior administration officials stress that the U.S. is maintaining open lines of communication with China and expressing its concerns with Beijing directly and privately.

Gordan Chang, a columnist, author and lawyer who wrote the book “The Coming Collapse of China,” said on NewsNation’s “Morning in America” that while the U.S. could freeze the accounts of every Chinese financial institution, the country has not been willing to do that. even though China “clearly has provided an economic lifeline to Vladimir Putin.”

“China’s already belligerent,” Chang said, and so the U.S’s warnings to it now “are a little bit late.”

“China doesn’t think the United States will impose sanctions,” Chang said. “Chinese leaders, for a very long time, have heard American presidents issue warnings, give advice all the rest of it, and never impose the crippling sanctions that we have promised. So Beijing just doesn’t believe us.”

In fact, Chang said, until the U.S. does impose these sanctions, “Beijing is just laughing.”