Prince Harry has been handed a three-word ultimatum in order to mend the rift with his family, a royal commentator has claimed.

Rupert Bell said the Duke of Sussex must "eat humble pie" after his older brother extended what some a calling an olive branch in his upcoming ITV documentary.

Mr Bell said "it would be odd" if William did not address his brother when discussing it with royal podcast host, Kinsey Schofield on her YouTube channel, discussing the future heir to the throne's upcoming documentary about homelessness, which will be aired tonight.

Critics have debated if the mention of Prince Harry, is a symbol of an olive branch from William to his younger brother, amid tense relations, following Harry stepping down as a working royal in 2020.

Rupert said: "It would be odd if he didn’t mention in this documentary, his brother [Prince Harry], you know, the back story. I’m sure he’s sad about the breakdown, because they were very close."

He added: "They looked after each other and that’s what’s so sad about it. The only way the olive branch is going to happen is if Harry eats some serious humble pie and says I’ve messed up."

Prince Harry detailed his private life and rifts between Royal Family members in his memoir Spare, and during his Netflix docuseries alongside his wife, Meghan Markle.

The documentary 'Prince William: We Can End Homelessness' will be available to watch on ITV and ITVX at 9pm on October 30 and 31.

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