Preparations for a huge party at the French home of Angelina Jolie and Brad Pitt have sparked fevered speculation that they are secretly preparing to marry.

Guests, including Brad Pitt’s parents, have arrived at the chateau ahead of the bash, to be held at Chateau Miraval this weekend.

Jeweller Robert Procop, who made Angelina Jolie’s $250,000 diamond and platinum engagement ring, is also thought to be in attendance.

The couple’s engagement was revealed back in April, after seven years and six children together.

A source told The Sun newspaper: “Brad flew in to oversee preparations but they’re all here now.

“They say it’s for Jane and Bill, but some think this could be it. Even Angelina’s private jeweller is here.”

Guests are said to include George Clooney, who is currently a short flight away at his home on Lake Como, Italy.

Preparations for a huge party at the French home of Angelina Jolie and Brad Pitt have sparked fevered speculation that they are secretly preparing to marry

The source added: “There’s a real buzz around the estate.”

It is thought that the couple will wed in a private chapel in the grounds of their home, with civil ceremonies only allowed at the town hall in France.

“We don’t know anything about it,” Patrick Mareschi, deputy culture secretary of the nearby village of Correns, told Reuters.

“Under French law couples have to get married at the town hall. Unlike with a religious wedding, there’s no way a couple can hold a civil ceremony at their own home,” he added.

It has long been known that the pair was planning to hold their wedding at their $55million estate in the South of France.

After their engagement was announced it was learnt that a huge reception hall was under construction at the Provence home.

Aerial images of the site in February showed a large white building being erected next to the quaint chapel.

Angelina Jolie has been married twice before – to British actor Jonny Lee Miller between 1996 and 1999 and then Billy Bob Thornton, from 2000 to 2003.

Brad Pitt’s marriage to Jennifer Aniston lasted five years before they announced they were divorcing in early 2005 – which came after he had met Angelina on the set of Mr. & Mrs. Smith.

Brangelina – as they became known – quickly became a Hollywood power couple, with a brood of six children, Maddox, 10, Pax, eight, Zahara, seven, five-year-old Shiloh and twins Knox and Vivienne, aged three.

The couple once insisted they wouldn’t wed until the legalization of same-sex marriage in America.

But Brad recently admitted he didn’t feel they’d be to wait that long because of mounting pressure from their children.

“It seems to mean more and more to our kids,” he said in January.

“We made this declaration some time ago that we weren’t going to [get married] till everyone can. But I don’t think we’ll be able to hold out … it means something to me, too, to make that kind of commitment.”

Angelina Jolie has also said that their children often ask why they aren’t married like “Shrek and Fiona”.

Angelina Jolie said just months ago: “We’ve explained to them that our commitment, when we decided to start a family, was the greatest commitment you could possibly have.

“Once you have six children, you’re committed.”