Prince Harry's Cressida the next royal bride?

‘They’ll make the engagement formal – if she can handle the attention’PRINCE Harry and girlfriend Cressida Bonas are already secretly engaged.

AISLE BE READY: Cressida has been seen out recently with Harry [GETTY]

The loved-up couple have a hush-hush agreement to tie the knot if she decides she can handle the attention that comes with being a royal girlfriend. And we can reveal Cressida has also been invited to spend some of the Christmas holidays with the royals at Sandringham. If all works out, the pair plan to announce the engagement in the spring and aim for a summer wedding. According to the Daily Star on Sunday, a royal aide said the couple will be seen out together more as they approach the 18-month mark in their relationship. “The deal is, once Cressida is happy with being a bride and a future princess they’ll announce their engagement,” said the aide.

“They have an understanding they’ll formally get engaged then, so long as she can handle the attention.” After deliberately laying low, society girl Cressida, 24, was spotted out in London with Apache pilot Harry, 29, for two nights running. First they were pictured at a James Blunt gig, then at the The Book Of Mormon musical. The couple are anxious to avoid a repeat of his parents’ marriage. Charles and Diana rushed in to a royal engagement after six months of dating, while Kate and William, both 31, waited ten years before marrying. The Palace insider said the love trial is “an old-fashioned Victorian-style betrothal”.

THUMBS Up: The Queen gives Harry the go ahead to invite Cressida for Christmas [GETT

In August we revealed how Harry and Cressida were expected to announce their engagement. Loved-up Harry had been joking “it could be any day now”, going out of his way to woo the babe. The royal seal of approval was Cressida’s invitation to Sandringham House for the traditional Christmas festivities. The Queen has given Harry the green light for his girlfriend to join them and Cressida is said to be “delighted”. Another insider said: “Cressida has been invited and it is highly likely right now she will go along. “She’ll go, if not on Christmas Day then on Boxing Day, to join Harry and the rest of the family. “The Queen has met Cressida and wants Harry to be happy.”

Kate’s parents Carole and Michael Middleton have also been invited to the festivities at the Norfolk estate this year. Wills spent last Christmas with his in-laws in Berkshire and this year will celebrate Prince George’s first Christmas. Both Wills and Harry are following Diana’s advice on finding a partner. She told them not to rush in and make sure they were best friends. “First you must find a girl who will be your friend, then wait,” she said. “Only when you’re sure of that friendship should you see if you can turn it into love.”