Multiple sources reveal that the A-list star and Charlotte Casiraghi - daughter of Princess Caroline, and granddaughter of the late Grace Kelly - have been quietly dating for more than a month after meeting through mutual friends.
The pair took their love public last week, both attending a Los Angeles Country Museum of Art event - with onlookers telling New Idea they were 'inseparable' and Brad was 'besotted' with his new princess.
'No-one could believe it when we saw them together,' and onlooker tells. 'There have been rumours circulating for weeks that Brad has moved on with a new woman, but no-one was ready to see him hand-in-hand with royalty from Monaco.'
It's believed Charlotte and Brad were introduced to one another by Brad's Allied co-star and good friend Marion Cotillard. Sources say the actress and Charlotte are very close friends, and after seeing Brad suffer through the last months of his marriage to Ange during filming for Allied and then their messy split, Marion was keen for him to find happiness.
The 31-year-old Charlotte has widely been regarded as a 'young Angelina Jolie' is sure to appeal to Brad, 53, as well. Fans have long made comparisons between the two women, with one follower commenting: 'Charlotte looks light years better than Ange did at that age.'
Friends say that aside from Brad and Charlotte's looks and famous backgrounds, the pair also have 'so much in common.'
As well as a love of horse riding, Charlotte is mum to Raphael, three - her son with French actor Gad Elmaleh - which appeals to dad-of-six Brad.
'They've both got kids and have been through high-profile splits, and Brad feels he can talk to Charlotte about anything,' says the source. 'Especially when it comes to his kids and his struggles to see them.'
For the full story see this weeks issue of New Idea - out now!