On Friday the two brothers unveiled a statue of their mother, Princess Diana, in Kensington Palace Gardens.
It was the first time they had seen each other since Prince Philip’s funeral in April.
Angela Levin, author of a number of royal biographies, argued the rift between William and Harry is unlikely to be fixed anytime soon.
Appearing on talkRADIO she said: “I think there will always be a frostiness and I think it will get worse if anything.
“I think he can’t do anything without his wife agreeing it and telling him and instructing him what to do at the moment.
“If he comes out of that situation things might improve but I think there’s no chance if he’s married to Meghan.
“I think she’s very controlling. I think his main aim, which is ok if he wants that, is to keep her happy.
“She’s a woman whose very difficult to keep happy because she has huge expectations and things are never enough.”
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The statue depicts Diana with her arms around two children, one male and the other female.
A third child is pictured further back, meaning the statue incorporates four figures in total.
Ms Levin claimed Harry was “putting on a huge phoney face” during the ceremony.
Diana was well known for her humanitarian and charity work during her life.
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