"The meeting?" Brooksbank asked the prince, according to the lip reader.
"It's sad. I'm fed up, I've tried talking to him," Harry apparently replied, though it's unclear who exactly he was talking about.
Brooksbank and Harry apparently chatted later on while they waiting for King Charles and Queen Camilla to arrive at Westminster Abbey.
Brooksbank then asked, "And is she?"
"It's not ideal," Harry replied.
"If it makes [you] feel any better even I can do it," Brooksbank is believed to have said. "It's not quite the life, is it?"
Harry then shook his head as Brooksbank said: "I haven't had time for that, not if it's over..."
"It's an eventuality," Harry said.
As OK! previously reported, Harry flew in for Charles' coronation without his wife, and though his relationship with his family is strained, he was all smiles as he walked into the event space with his cousins Eugenie and Princess Beatrice.
After the ceremony concluded, Harry quickly got into a car and went to the airport to go home so he could be with his son, Archie, on his fourth birthday.
According to an insider, some relatives "breathed a sigh of relief" that Harry wouldn't be staying around, but the King was "genuinely quite disappointed that he didn’t stay."
At a luncheon following the ceremony, Charles said some kind words about his grandchild. The former Prince of Wales raised a glass to "those that weren’t there" and wished Archie a very happy birthday "wherever he was."
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Daily Star reported on Harry's chat.