President Donald Trump secretly left last month's NATO summit in Ankara, Turkey, on an alternate military aircraft because of a reported threat from Iran, according to a Washington Post report. The White House made it appear that Trump was flying on Air Force One, but the president actually switched planes using a catering cart, the report said. The swap was done without the knowledge of the travelling press pool and some White House staff. The threat, which the report did not specify, prompted an undisclosed change in the president's travel plans. Trump had been in the Turkish capital for the NATO gathering. The Post cited unnamed officials for its account. After the report was published, France 24 and Al Jazeera relayed the details. The White House and Secret Service have not publicly commented. The extra security measure shows how seriously the administration viewed the threat, though no further details were available.