Donald Trump alleged “triple sabotage” at the United Nations, after the US president was plagued by a series of unfortunate events surrounding his address to the global body.

“A REAL DISGRACE took place at the United Nations yesterday,” Trump wrote in a 357-word post on his social media platform, Truth Social, on Wednesday. “Not one, not two, but three very sinister events!”

According to Trump, his smooth arrival at the summit in New York on Tuesday was disrupted when the escalator ferrying him and the first lady to the General Assembly Hall “stopped on a dime”. He expressed surprise that the first couple “didn’t fall forward onto the sharp edges of these steel steps, face first”.

Then, his teleprompter went “stone cold dark”.

“I immediately thought to myself, “Wow, first the escalator event, and now a bad teleprompter. What kind of a place is this?’” Trump wrote. Adding insult to injury, he recounted a third alleged offense: after being forced to improvise part of his speech to the general assembly, he asked Melania Trump how he had done, she replied: “I couldn’t hear a word you said.”

“This wasn’t a coincidence, this was triple sabotage at the UN,” Trump declared, demanding an “immediate” investigation into the matter, a scandal so Trumpian it has earned the name “escalatorgate”.

“All security tapes at the escalator should be saved, especially the emergency stop button. The Secret Service is involved,” he concluded. “Thank you for your attention to this matter!”

Earlier on Wednesday, the UN responded to the incident in a statement to correspondents, titled “on UN escalators”.

Stéphane Dujarric, the UN spokesperson, said an investigation indicated that a videographer from the US delegation who had run ahead of the first couple to document their arrival may have “inadvertently triggered the safety function” designed to prevent people or objects from accidentally getting caught in the mechanism.

“As the videographer, who was traveling backwards up the escalator reached the top , the First Lady, followed by President Trump, each mounted the steps at the bottom,” Dujarric said. “At that moment (9:50am), the escalator came to a stop. Our technician, who was at the location, reset the escalator as soon as the delegation had climbed up to the second floor.”

Footage showed the 79-year-old president and the 55-year-old first lady stepping onto the escalator at UN headquarters, before it lurched to a stop. They both tighten their grip on the handrails as they turn around quickly to see what caused them to stall. Then Melania Trump begins to climb the steps, followed by her husband.

Trump’s Wednesday post suggests the president does not accept the UN’s conclusion into the mishap on the moving stairway and believes there was a wider conspiracy afoot.

While technical difficulties might have beset his delivery from behind the green marble lectern on Tuesday, Trump’s address was heard loud and clear around the world. In a combative speech, Trump bashed the UN and warned European allies that unless they curbed migration, their countries were “going to hell”.

During his speech, Trump swerved from his remarks to address his fateful entrance and, in his view, poor treatment at the assembly.

“All I got from the United Nations was an escalator that on the way up stopped right in the middle,” he said. “If the first lady wasn’t in great shape, she would have fallen, but she’s in great shape. We’re both in good shape, we’re both still. And then a teleprompter that didn’t work. These are the two things I got from the United Nations, a bad escalator and a bad teleprompter.”

However, it seemed unlikely that the audio problem was as bad as Trump made it out to be since video of the room during his speech shows the audience reacting immediately to what he was saying.

Later that evening, White House press secretary Karoline Leavitt alleged on Fox News that the elevator stoppage was part of an intentional plot to humiliate the US president.

“If we find that these were UN and staffers who were purposefully trying to trip up, literally trip up the president and the first lady of the United States, well, there better be accountability for those people. And I will personally see to it,” she said.

In his lengthy post on Wednesday afternoon, Trump pointed to a report in the Times of London newspaper on Sunday saying that UN staff members had joked that they would turn off the escalators and “tell him they ran out of money” – a jab at the sweeping US funding cuts.

“The people that did it should be arrested!” Trump wrote.