“All I got from the United Nations was an escalator that on the way up stopped right in the middle,” he mused, chopping the air with his hand.

But it turns out the cause was closer to Trump.

Stephane Dujarric, the UN spokesman, said a videographer from the US delegation who ran ahead of him triggered the stop mechanism at the top of the escalator.

“The safety mechanism is designed to prevent people or objects accidentally being caught and stuck in or pulled into the gearing,” Dujarric said in a statement.

“The videographer may have inadvertently triggered the safety function.”

As he began his speech, Trump also noted that the teleprompter wasn’t working. He joked that whoever was running the teleprompter “is in big trouble.”

A UN official speaking on condition of anonymity because of the sensitivity of the issue contributed that one to his side as well, saying the White House was operating the teleprompter for the president.

Regardless of the cause, it’s not unusual for escalators at the UN to stop working, as staff and visitors know quite well.

In recent months, UN offices in New York and Geneva have intermittently turned off elevators and escalators as part of steps to save money because of a “liquidity crisis” at the world body.

That’s due in part to delays in funding from the US, which is the top donor of the world body.