The German Chancellor was already on her way to the airport on Monday ready to fly to Washington when the plug was pulled on the trip.
The President postponed the trip as the northeast of America prepared to be hit by a huge winter storm.
Snowstorm Stella has prompted airlines to cancel thousands of flights and some mayors to order schools to close on Tuesday.
The White House later said the visit would be rescheduled for Friday.
Merkel continued to Berlin's Tegel airport after her 10-minute conversation with Trump to personally inform reporters who were due to travel with her to Washington of the change of plan.
"The trip is cancelled. That is not a joke," Merkel told the dozen or more surprised reporters already seated on board the government's Airbus A340 plane.
Merkel had been due to meet Trump for more than two hours on Tuesday, followed by a working lunch.
Top executives from three German companies, including engineering group Siemens and carmaker BMW, who had been due to travel with Merkel, would also participate in the postponed trip, officials said.
Merkel is no stranger to weather-related travel changes.
In 2010, she was stranded during a trip to the United States following the eruption of a volcano in Iceland and had to follow a circuitous route home via Portugal and Italy.
In 2012, France's newly elected Socialist President Francois Hollande was en route to meet Merkel, a conservative, but had to return to Paris after his plane was struck by lightning, an incident that helped break the ice in the relationship between the two leaders despite their political differences.
German government officials said the abrupt postponement of Merkel's trip to Washington could act in the same way for her and Trump, providing an unexpected personal kickstart for discussions that will centre on complex and difficult issues, including trade issues, Russia, NATO and the Middle East.