President Joe Biden says he’s warned his Chinese counterpart Xi Jinping that violating U.S. sanctions imposed on Russia for its invasion of Ukraine would be a “gigantic mistake” that may hurt investment in China.

In an interview with CBS on Sunday, Biden said that he spoke with Xi not long after the Chinese leader signed a “no limits” partnership with Russian President Vladimir Putin during the Beijing Winter Olympics in February.

“And I said that if you think that Americans and others were going to continue to invest in China based on your violating the sanctions that have been imposed on Russia, I think you’re making a gigantic mistake. But that’s your decision to make,” he said.

Biden emphasized that he was not threatening Xi but rather warning him of the ramifications of violating the sanctions on Russia. He said there has been no indication thus far that China has offered weaponry in support of Russia.

Washington imposed a slew of sanctions on Russia to ramp up pressure on the Kremlin to halt its aggression in Ukraine. The European Union and several other countries have also followed suit.