President Donald Trump's United Nations speech was a snooze — at least for Commerce Secretary Wilbur Ross.

The 81-year-old Ross took a nap — a very long nap — as his boss addressed the U.N. General Assembly on Tuesday.

Television footage of Ross showed the wealthy businessman sleeping soundly as Trump talked about a possible trade deal with China — which is part of the Commerce chief's portfolio — and the U.S. stance on Iran.

Ross had his eyes firmly closed for as long as 15 minutes, video suggested, as Vice President Mike Pence and Secretary of State Mike Pompeo gave the impression of listening intently to Trump.

At one point, however, Ross's eyes opened. He still looked drowsy, though.

"This is fake news," Ross said in a statement issued to CNBC by the Commerce Department, hours after this article first was published.

"I wear hearing aids and, during President Trump's inspiring speech, which covered in detail the entire range of significant issues facing the world, was concentrating on what was being said," Ross said.

"Immediately following the President's remarks, I attended bilateral meetings with the leaders of the United Kingdom and India, and, later in the day, will have follow-up meetings with officials from the United Kingdom and South Korea," Ross said.

"Additionally, throughout the entirety of the UN General Assembly, I attended events or am planning to participate in meetings with the governments of Pakistan, Poland, Egypt, Japan, Greece, and Vietnam."

"On Sunday, I will depart on twelve days of official travel to London, New Delhi, Bengaluru, Yangon, Naypyitaw, Canberra, and Sydney."

"This is not the schedule of someone with low energy."

Despite Ross's protestations to the contrary, this would not be the first time that he was caught out catching 40 winks while Trump gives a speech.

Video from Trump's speech in Saudi Arabia in May 2017 showed Ross napping with headphones on, several seats away from the president's daughter, Ivanka Trump.

Politico in July published a scathing article that suggested the Commerce Department was "a disaster," and quoted one former department adviser who said Ross was "not respected in the building" in part because of his lack of stamina.

"Because he tends to fall asleep in meetings, they try not to put him in a position where that could happen so they're very careful and conscious about how they schedule certain meetings," the former outside adviser told Politico.

"There's a small window where he's able to focus and pay attention and not fall asleep."

Ross disputed Politico's account in a tweet after the article ran.

Ross Tweet: Today's @Politico report bears no resemblance to reality and appears to be solely sourced from disgruntled former employees whose poor performance led to their departures.

Ross's latest cat nap came a day after another awkward video moment for Team Trump at the U.N.

Trump was clearly surprised Monday when Treasury Secretary Steven Mnuchin told reporters in front of Trump that it was U.S. officials who had asked members of China's trade delegation to cancel a scheduled farm tour in the United States last week, and not the Chinese.

Trump asked Mnuchin, with a strained chuckle, "Why was that our request, just out of curiosity?"

"We didn't want confusion around the trade issues," Mnuchin said.

Trump replied: "Yeah, but I want them to buy farm products."

WATCH: Trump questions Mnuchin over canceled Chinese farm tour