Prince William, Prince Harry break special promise made to Princess Diana

Prince Harry and Prince William could not keep the promise they made to their late mom Princess Diana by cutting ties with each other.

According to royal correspondent Michael Cole, the former Princess of Wales made her sons promise to each other that they would "always be friends."

However, the brothers could not uphold the promise as they stopped talking to each other after the Duke of Sussex leaked their private fights in his explosive memoir Spare.

Speaking with GB News, the expert said he "feels sorry" for Harry as no member of the Royal family would attend the 10th anniversary event of his Invictus Games.

"I feel sorry for Harry because he says he loves this country. It's his home and he loves Britain,” he said, adding, "You know what makes me saddest of all? I think of Diana, Princess of Wales, the late, the much missed Diana."

"When those boys were quite young, she made them promise to each other that they would always be friends, that they would always be there for each other, and they made that promise,” Cole revealed.

"It really does make me sad, and I hope that he [Harry] has time to ponder that when he comes back here. There are few worse sights in the world than seeing brothers fighting.”

“And when it's brothers of the royal blood, when it's princes fighting, that's so much worse and it's so regrettable. And actually, it's all so unnecessary."