GEORGE CLOONEY faces a devastating wedding disaster, including an as-yet-not finalized $220 million wedding contract his lawyers have been negotiating and “fighting” with his bride-to-be’s legal team.

What’s more, the couple’s wedding planner has quit, there’s squabbling over the guest list – and friends fear the whole thing may derail, sources dish to The ENQUIRER .

The 53-year-old “Michael Clayton” star plans to tie the knot with stunning British lawyer Amal Alamuddin, 36, in September at his Lake Como home in Laglio, Italy.

But without a prenup in place, all bets could be off, sources say. “Clooney is worth an estimated $220 million,” famed New York divorce lawyer Raoul L. Felder told The ENQUIRER .

“Given his shaky track record with women over the years, including a difficult divorce from his first wife and the brief longevity of most Hollywood marriages in general, I think he needs to make sure he has a prenuptial agreement that’s ironclad.

“He has a lot to worry about and a lot to lose if he doesn’t proceed with the utmost care and caution. The fact that (his fiancée) is a lawyer is strike one against him. I expect his lawyers are being very careful and ‘fighting’ her lawyers over every point.”

It’s an ominous sign that the couple is already at loggerheads over the guest list, fluctuating from a small intimate affair to a big A-list blowout, say sources. On top of that, their wedding planner quit in a huff after George changed wedding venues from Lake Como to Venice and then back to the original site.

“Before switching locations, George told the planner he wanted a sponsor,” claimed a close source, “Now it all seems disorganized.” Even something as simple as the guest list is causing headaches.

The ENQUIRER has learned that after dragging her feet, Angelina Jolie has finally decided to attend.

“At first she was on the fence about going, because she’s not big on schmoozing at Hollywood get-togethers,” said a source. “But she quickly changed her mind after George told her that President Obama RSVP’d ‘Yes’!” “Before that, she didn’t want Brad (Pitt) to go, either. But Brad, being such good friends with George, was going with or without her.”

A potential battle of superstar egos could also mar the festivities – Jennifer Aniston vs. Angelina. As The ENQUIRER was first to report – back in July – both Brad’s current lover as well as his ex-wife are on the guest list – for now anyway, according to a source.

“George is extremely concerned that by inviting both these women, they’ll undoubtedly try to upstage each other and in so doing take the spotlight off the bride.”

As if George did not have enough to worry about, he was desperately hoping to keep under wraps his bitter first marriage to actress Talia Balsam!

Back in 1992, when George filed for divorce to end the acrimonious four-year union, he was a struggling actor. Documents reveal haggling over a number of assets, including a 1988 Saab, a 1959 Corvette and a Harley Davidson motorcycle. Also at stake were a 1988 Dodge and a motor home, which would eventually go to George. A queen-size bed and box spring ended up with Talia.

“Amal may have little idea just how contentious her future hubby’s divorce was,” warned a source. And a pal of the actor – who already has obtained his marriage license – noted: “What should be a joyous time for the couple is instead filled with tension and short fuses. There’s a lot of second guessing going on. In fact, if their big day goes off without hitch, it will truly be a miracle.”