A lip reader has uncovered a tense moment between Prince Harry and Prince William during their final joint appearance before Harry and Meghan stepped back from royal duties.

Harry and Meghan, who officially left the Royal Family in 2020, had taken part in many formal events together during their time as working royals.

One of their last public appearances was at the Commonwealth Day ceremony at Westminster Abbey on March 9 that year, just before they moved to Canada and later to the United States.

It was during this event that Harry was reportedly overheard making a sarcastic comment about his older brother to Meghan.

Despite ongoing tensions — especially after Harry and Meghan accused certain royals of mistreatment — the two brothers maintained a polite front in public at the time.

Prince Harry and Meghan Markle met up with with Prince William and Kate Middleton (Chris Jackson / Staff / Getty)

At Westminster Abbey, fans noticed a brief exchange where William greeted with a “Hello Harry,” and Harry replied with a simple “Hello,” before lip reader Jeremy Freeman shared the rest of the conversation with The Daily Star.

Meghan reportedly greeted Catherine with a friendly “hi” and gave William a “hello,” although he seemed not to notice her at first.

Harry then turned to Meghan and, according to the lip reader, said: “At least they acknowledged, unlike last time.”

William later spoke to Catherine, allegedly saying: “That was executed well.”