Air Force One was forced into an emergency U-turn in the middle of the night - just as Donald Trump was heading to Davos.
Mr Trump's presidential plane had only just jetted out over the Atlantic when it was forced into a 180-degree turn.
He had left for Zurich just after 9.30pm, but was back where he started fewer than two hours later.
"America will be well represented in Davos - by me. GOD BLESS YOU ALL!" the President wrote on social media after take-off.
But his highly-modified Boeing 747 had to return to Joint Base Andrews in Maryland after crew discovered an "issue" aboard.
Lights had flickered in the cabins - though precious few details were given out.
Footage on social media showed police-escorted vehicles storming down a motorway to meet the plane as it came in.
The fault was later identified as "a minor electrical issue" which was found shortly after take-off.
Mr Trump's presidential plane had only just jetted out over the Atlantic when it was forced into a 180-degree turn
|ADSBEXCHANGE
Just before departure, Mr Trump said "there can be no going back" on his plan to seize Greenland from Denmark.
Mr Trump's trip to the World Economic Forum in Switzerland may now be delayed, with the President continuing his trip on a new aircraft, White House Press Secretary Karoline Leavitt said.
At the WEF, Mr Trump is due to meet European leaders after plunging the Nato alliance into what some have billed as its greatest crisis in history.
He told reporters on Tuesday night that he would "work something out where Nato is going to be very happy and where we're going to be very happy".
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The highly-modified Boeing 747 had to return to Joint Base Andrews in Maryland
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There are "a lot of meetings scheduled on Greenland", he added.
But the island, which falls under the Nato umbrella as an autonomous part of Denmark, is in uproar over his plans.
Its Minister of Industry and Natural Resources, Naaja Nathanielsen, said locals were "bewildered" by the President's demands.
At the WEF, Mr Trump is due to meet European leaders after plunging the Nato alliance into what some have billed as its greatest crisis in history
|GETTY
"We do not want to be Americans, and we have been quite clear about that," she told the BBC.
Meanwhile in the Arctic, Greenlanders have been urged to start stockpiling five days of supplies to prepare for a possible conflict.
Mr Trump insisted that "things are going to work out pretty well" in the territory, however.