The US Senate Republican leader, Mitch McConnell, appeared to freeze mid-sentence and stare into space for around 20 seconds during a press conference.
The 81-year-old approached the podium for his weekly press conference and began speaking about the annual defense funding bill before appearing to lose his train of thought and trailing off with a drawn-out “uh”.
He then appeared to stare vacantly into space for around 20 seconds, before his Republican colleagues grabbed his elbows and asked if he wanted to go back to his office.
He did not answer but slowly walked back to his office with an aide and the senator for Wyoming, John Barrasso.
Mr McConnell was out of the Senate – the upper chamber of Congress – for almost six weeks earlier this year after he fell and hit his head after a dinner event at a hotel.
He was in hospital for several days and his officer later said he suffered a concussion and fractured a rib.
His speech has sounded more halting in recent weeks, prompting questions about his health.