US President Donald Trump departed on a secret military flight from Turkey last month when the White House said he was flying aboard Air Force One, an extraordinary move prompted by an Iranian assassination threat, the Washington Post reported Monday.

Trump had taken the newly renovated Qatari-donated jet to Ankara for the NATO summit but he unexpectedly used an older Air Force One when departing the country, a move that prompted questions about the newer plane’s security.

The trip to NATO was the first international travel for the new plane, whose speedy upgrades triggered questions over its cost and security, and took place as hostilities escalated with Iran, which borders Turkey.

Before departing Ankara, Trump said on Truth Social that he would use an older baby blue Air Force One plane “for old time’s sake” to RAF Mildenhall in Britain while the new plane stopped at the same base so US service members stationed there could tour the aircraft.

After Trump ⁠boarded the old Air Force One in front of cameras in Ankara, he was secretly shuttled by an airport catering truck to a smaller plane, an Air Force C-32A, the Post reported, citing a US official familiar with the operation and corroborating material it reviewed.

The deception operation was triggered by a credible threat to Trump, the Post reported. A similar operation had taken place in 2000, when President Bill Clinton used an unmarked executive jet to fly into Pakistan while sending his formal Air Force One as decoy.

On this occasion, the journalists who thought they were traveling with Trump on the older Air Force One, which was effectively used as a decoy, reported being advised to keep their window shades in the press cabin closed. The Post said aside from reporters, some White House staff also believed that the president was on board.

When asked later by reporters why they had to keep their shades shut during the flight, Trump said it was ⁠because they were “probably on a dangerous flight.” He went onto say: “But if I go, you go. Right?”

The C-32A carrying Trump flew to Britain and arrived at around 10:20 p.m. while the older Air Force One and media, arriving minutes later, the Post reported. It was not clear, the paper said, how Trump was moved from the C-32A back to the older Air Force One.

Trump’s travelling press pool reported he climbed down the stairs of the older Air Force One at 10:56 p.m. UK local time.

He gave press ⁠a peace sign but didn’t walk over to talk to them. He then spent some time greeting service members before walking to the new, Qatar-donated plane.

When asked for comment on the revelation of a secret flight on a third plane, the White House provided a statement from Communications Director Steve Cheung saying the Qatari-donated jet has been fitted with ⁠high-level security protocols that ensure the safety of the president and his staff.

“As the President has said recently, there are many enemies of America who have their sights on him, and we use every tool at our disposal to address those threats,” Cheung said. It was the same statement provided to the Post.

The ⁠Pentagon did not immediately respond to a request for comment.

The new plane, with red, white, dark blue and gold livery chosen by Trump, is a Boeing 747 gifted to the United States by Qatar last year and refitted by defence contractor L3Harris Technologies. It was intended to serve as a temporary placement while Boeing (BA.N) struggled to deliver long-delayed next-generation Air Force One planes.