Following a NATO summit in Ankara, Trump was transferred from Air Force One to a military plane via a catering truck in an extraordinary deception prompted by an Iranian assassination threat, US media reported.
The White House did not disclose the change and it remained a secret until the Washington Post first reported it on Monday.
Some media commentators questioned whether the operation left Trump's aides and journalists travelling with him at risk aboard the plane presumed to be carrying the president.
"I think actually the plane that I flew on was at greater risk," Trump told reporters on Tuesday.
"I think it was at greater risk because that would be the plane I think that they would be more likely to go for."
After a day of social media memes portraying Trump as hiding out in the catering truck, the image-conscious president, who often promotes memes of himself as a bold and courageous leader, said he was following the direction of the Secret Service, the agency that protects the president.
"Well, it's only up to Secret Service. I just follow what they'd like to do, so I go by Secret Service and the military," Trump said.
"I guess there was a threat out there. I didn't really ask too much about it. I get a lot of threats," Trump said.
The White House said at the time that the president was flying aboard Air Force One from Turkey to Britain.
But moments after Trump boarded the plane, he left it in secret via the catering truck and boarded another aircraft for the flight to Britain, the Post said on Monday, quoting unnamed sources.
Trump had taken a newly renovated Qatari-donated jet to Ankara for the NATO summit but unexpectedly announced he would use 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.
