The Trump administration is preparing to accept a superluxury Boeing 747-8 jumbo jet from the royal family of Qatar as a gift to be used by President Donald Trump as the new Air Force One for presidential travel until shortly before Trump leaves office, according to four sources familiar with the planning.

A deal on a plane that would become Air Force One has not been reached, but ethics experts say accepting it from Qatar would violate the Constitution’s emoluments clause.

Some of Trump’s staunchest supporters are among the loudest critics of his plan to accept a jet from Doha for use as Air Force One.