The Pentagon says it has accepted a $400 million jet from Qatar that will be retrofitted to become Air Force One. Air Force One is the call sign for any Air Force airplane that transports the president of the United States.

President Donald Trump previously defended the move, saying, “I could be a stupid person and say, ‘No, we don’t want a free, very expensive airplane.’” He stated that the plane would ultimately be transferred to his presidential library after he leaves office.

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“The Secretary of Defense has accepted a Boeing 747 from Qatar in accordance with all federal rules and regulations. The Department of Defense will work to ensure proper security measures and functional mission requirements are considered for an aircraft used to transport the President of the United States. For additional information, we refer you to the United States Air Force,” said chief Pentagon spokesman Sean Parnell. “I wouldn’t be using it,” he added.

Democrats have decried the acceptance of the jet for a multitude of reasons, including safety concerns. They are also worried about the costs associated with retrofitting the airplane into a presidential transport.

In a prior interview with Scripps News, Sen. Angus King, an independent who caucuses with Democrats, said accepting the airplane is “crazy on every level.” “We’d practically have to take it apart piece by piece to be sure it’s not compromised in some way,” he said.

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A Secret Service source told Scripps News that securing the jet will be the responsibility of the Air Force.

"They are going to make sure that there’s no counter surveillance stuff or issues with the plane," the source said. The source added that the Air Force would be the agency "stripping" the plane, but the Secret Service will probably do it's own security assessment of the plane at some point.

The Secret Service source noted that Air Force pilots would need to be trained on flying this sort of Boeing jet, as it is a different plane than those within the current presidential fleet.