Prince Harry is reportedly begging his brother Prince William not to marry Kate Middleton, because he believes it’ll all end in tears.

A marriage proposal is said to be in the works after William and Kate got back together earlier this month after their previous split - but Harry is against the marriage, worried that it might be a case of history repeating itself.

A so-called royal insider told the National Enquirer: “Wills finally caved into a marriage ultimatum from Kate as a condition of getting back together.”

“Kate is asking Wills to set a date for the engagement, but Harry wants his brother to take his time and make sure he’s 100 percent certain.

“The boys loved their mother with all their heart, but now they’re grown up and realize it was a mistake for Charles to allow himself to be pressured into marrying Di when he didn’t really want to.”

“A lot of people - Harry included - think William is clinging to the only girl he has ever come close to having a serious relationship with.”

William and Kate met at university in 2001 but didn’t become a couple until 2003. After splitting in April, they are thought to have reconciled in secret before officially getting back together earlier this month.

Kate, said to be well liked within the royal family, attended William’s step-mother Camilla’s 60th birthday party yesterday. Around 200 family and friends attended the black-tie party at Highgrove thrown by Prince Charles in honour of his wife.

According to the Daily Express, Kate had initially denied that she would be attending but then stayed at the event until the early hours of this morning.

A source told the Sun the couple were inseparable during the party: “They seemed to be in their own little world and barely seemed to be apart. You would have struggled to fit a postage stamp between them.”

“William couldn’t take his eyes off her. Whatever problems they had are clearly sorted.”