arrived hand-in-hand for a star-studded party in Malibu on Sunday tocelebrate Bono's birthday and their recent engagement
. The happy couple were pictured arriving at Cafe Habana, where they joined the likes ofCindy Crawford
, her husbandRande Gerber
, who owns the restaurant, and U2'sThe Edge
.The celebrity group gathered on the back patio, where theytoasted George and Amal with tequila and wine
"After the toast, George and his fiancée were all over each other,
" a source toldPeople
. "Lots of hugging
."Smiling Amal could be seenshowing off her impressive seven-carat diamond engagement ring
as she chatted with her husband-to-be's close friends.There was even a bit of karaoke;Bono got up and sang during the party, as did supermodel Cindy
, who reportedly duetted with her daughter Kaia.
An eyewitness toldE! News
that the venue was busy with people celebrating Mother's Day. "They got a show they didn't expect andother (restaurant patrons) said it was the best Mother's Day ever
to British human rights lawyer Amal, 36, in late April, after seven months of dating.The future Mr and Mrs Clooney recently returned from a holiday in Cabo, Mexico, where they celebrated a friend's wedding. "You can tell these two are in love," an onlooker said.