The Defence Department intends to “implement necessary security precautions” to ensure the jet is suitable for the president’s use, stated Pentagon spokesman Sean Parnell on Wednesday (Thursday AEST). He mentioned that the acceptance of the plane was conducted “in compliance with all federal statutes and guidelines.”

Trump has defended the gift, which came up during his recent Middle East trip, as a way to save tax dollars.

“Why should our military, and thus our taxpayers, be burdened with paying hundreds of millions of dollars when they can obtain it for FREE?” Trump posted on his social media platform during the visit.

Others, however, have said Trump’s acceptance of an aircraft that has been called a “palace in the sky” is a violation of the Constitution’s prohibition on foreign gifts. Democrats have been united in outrage, and even some of the Republican president’s GOP allies in Congress have expressed concerns.

“This unprecedented action is a stain on the office of the presidency and cannot go unanswered,” said Senate Democratic Leader Chuck Schumer.

“Until Americans get transparency on this shady deal, which apparently includes a corrupt plot for Donald Trump to keep the plane at his library after leaving office, I’ll continue to hold all Department of Justice political nominees.”

Schumer has introduced legislation that would prohibit any foreign aircraft from being used as Air Force One and forbid use of taxpayer money to modify or restore the aircraft. But on Wednesday, Republican Senator Roger Marshall objected when Schumer asked for a vote, thus blocking it. He did not offer an explanation for his objection.

Critics also have noted the need to retrofit the plane to meet security requirements, which would be costly and take time.

“Far from saving money, this unconstitutional action will not only cost our nation its dignity, but it will force taxpayers to waste over $1 billion in taxpayer dollars to overhaul this particular aircraft when we currently have not one, but two fully operational and fully capable Air Force One aircraft,” said Democratic Senator Tammy Duckworth.

She said during a hearing on Tuesday that it is a “dangerous course of action” for the US to accept the aircraft from the Qatari ruling family.

US Air Force Secretary Troy Meink told senators that Hegseth has ordered the service to start planning how to update the jet to meet needed standards and acknowledged that the plane will require “significant” modifications.

The US Air Force, in a statement, said it is preparing to award a contract to modify a Boeing 747 aircraft, but that any details are classified.

Trump was asked about the move on Wednesday while he was meeting in the Oval Office with South African President Cyril Ramaphosa.

“They are giving the United States Air Force a jet,” Trump said, bristling at being questioned about the gift by a reporter.

Trump said it was given “not to me, to the United States Air Force, so they could help us out” and noted that “Boeing’s a little bit late, unfortunately.”

Trump has presented no national security imperative for a swift upgrade rather than waiting for Boeing to finish new Air Force One jets that have been in the works for years.

He has tried to tamp down some of the opposition by saying he wouldn’t fly around in the aircraft when his term ends. Instead, he said, the plane would be donated to a future presidential library, similar to how the Boeing 707 used by former president Ronald Reagan was decommissioned and put on display as a museum piece.