The Qatari government acknowledged discussions between the two countries about "the possible transfer" of a plane to be used temporarily as Trump's Air Force One, but denied the jet "is being gifted" and said no final decision had been made.
In a post on his social media site Truth Social, Trump appeared to confirm the proposal.
"So the fact that the Defense Department is getting a GIFT, FREE OF CHARGE, of a 747 aircraft to replace the 40 year old Air Force One, temporarily, in a very public and transparent transaction, so bothers the Crooked Democrats that they insist we pay, TOP DOLLAR, for the plane," he wrote.
White House press secretary Karoline Leavitt said in a statement, "Any gift given by a foreign government is always accepted in full compliance with all applicable laws. President Trump's administration is committed to full transparency."
ABC News reported that Trump will use the plane as a new version of Air Force One until shortly before he leaves office in January 2029, when ownership will be transferred to the foundation overseeing his yet-to-be-built presidential library.
The gift was expected to be announced when Trump visits Qatar as part of a trip that also includes stops in Saudi Arabia and the United Arab Emirates, the first extended foreign travel of his second term.
But hours after the news, Ali Al-Ansari, Qatar's media attache, in a statement said, "Reports that a jet is being gifted by Qatar to the United States government during the upcoming visit of President Trump are inaccurate."
"The possible transfer of an aircraft for temporary use as Air Force One is currently under consideration between Qatar's Ministry of Defence and the US Department of Defence," the statement said.
"But the matter remains under review by the respective legal departments, and no decision has been made."
Meanwhile, administration officials, anticipating questions about the president accepting such a large gift from a foreign government, have prepared an analysis arguing that doing so would be legal, according to ABC.
The Constitution's Emoluments Clause bars anyone holding government office from accepting any present, emolument, office or title from any "king, prince, or foreign state", without congressional consent.
One expert on government ethics, Kathleen Clark of the Washington University School of Law in St Louis, accused Trump of being "committed to exploiting the federal government's power, not on behalf of policy goals, but for amassing personal wealth".
"This is outrageous," Clark said.
"Trump believes he will get away this."
Senate Minority Leader Chuck Schumer poked fun at Trump's "America first" political slogan.
"Nothing says 'America First' like Air Force One, brought to you by Qatar," the New York Democrat said in a statement. "It's not just bribery, it's premium foreign influence with extra leg room."
Trump intends to convert the Qatari aircraft into a plane he can fly on as president, with the Air Force planning to add secure communications and other classified elements to it.
But it will still have more limited capabilities than the existing planes that were built to serve as Air Force One, as well as two other aircraft currently under construction, according to a former US official.
ABC said the new plane is similar to a 13-year-old Boeing aircraft Trump toured in February, while it was parked at Palm Beach International Airport and he was spending the weekend at his Mar-a-Lago club.
