Former president Donald Trump doubled down Wednesday on his alarming criticism of U.S. NATO allies after President Joe Biden said his remarks were “un-American.”

Trump on Saturday asserted that, if reelected, he would let Russia do “whatever the hell they want” to NATO members that did not “pay their bills.”

It was a faulty claim, as the 75-year-old treaty organization does not work the way Trump implied.

He nevertheless hammered on, writing on Truth Social, “Could somebody please inform our uninformable President that NATO has to pay their bills!”

“They should equalize with the U.S. - FAST! The European Nations, when combined, have approximately the same size Economy as we do. They have the money. PAY UP!”

NATO receives some direct funding from member nations, but it is largely backed by indirect funding. The group is strengthened when each nation invests in its own military.

In 2014, member nations decided that those not spending at least 2% of their gross domestic product on defense would attempt to reach that goal within 10 years. NATO is not close to meeting that goal, but there are no “bills” that become “delinquent,” as Trump asserted at a rally in South Carolina on Saturday.

He has repeatedly portrayed himself as a driving factor of NATO’s increased funding, even though member nations had pledged to do so two years before he was elected.

Biden ripped into Trump’s NATO criticism on Tuesday, saying the U.S. commitment to the organization was “sacred.”

“When he looks at NATO, he doesn’t see the alliance that protects America and the world. He sees a protection racket. He doesn’t understand that NATO’s built on a fundamental principles of freedom, security and national sovereignty, because for Trump, principles never matter. Everything is transactional,” Biden said.