President Donald Trump angrily brushed off ethical concerns about accepting a $400 million luxury jet from Qatar to be used as a new Air Force One, saying only someone “stupid” would turn down such an offer.

“I think it’s a great gesture from Qatar. I appreciate it very much,” Trump said. “I would never be one to turn down that kind of an offer. I mean, I could be a stupid person say, ‘No, we don’t want a free, very expensive airplane.’ But it was — I thought it was a great gesture.”

Qatari officials say the plan for Trump to accept the plane for use as Air Force One while he’s in office is not finalized. Some senior U.S. officials, however, have openly described it as an eventuality, one signed off on by the White House counsel and Attorney General Pam Bondi. Trump has repeatedly complained of delays and cost overruns in a contract with Boeing for two new presidential jets.

But on Monday Trump said when the Qatari plane is decommissioned from military use and is turned over to his library at the end of his term that he won’t continue flying in it.

He grew angry at the questions of an ethical quagmire, including whether Qatar expected anything in exchange for the donation, which he said would be to the Defense Department and not to him personally. Democrats and government watchdogs have suggested the donation would violate the Emoluments Clause of the Constitution, and create an incentive structure for Trump regarding Qatar.

“You should be embarrassed asking that question,” Trump told an ABC News reporter who pressed him on the issue. “They’re giving us a free jet. I could say, ‘No, no, no, don’t give us. I want to pay you a billion or $400 million, or whatever it is.’ Or I could say, ‘Thank you very much.’ ”

He then invoked a golf analogy about accepting a free putt during a round, suggesting that following rules when one doesn’t have to is foolish.

Trump’s own private plane, known as “Trump Force One,” is a 757 jet that first flew in the early 1990s and was then used by Microsoft co-founder Paul Allen. Trump bought it in 2011.

While Trump faced criticism during his first term for the way his properties collected money from the government, the last four months have included a flurry of deals around a cryptocurrency firm that has erased centuries-old presidential norms.

“Even in a presidency defined by grift, this move is shocking,” said Robert Weissman, a co-president of Public Citizen, a consumer advocacy organization. “It makes clear that U.S. foreign policy under Donald Trump is up for sale.”