JENNIFER LOPEZ will celebrate her 40th birthday on Friday (24Jul09) with a spectacular bash in her native New York.

A starstudded event is being planned on Saturday night (25Jul09) to mark the milestone, which will blow away the party her husband Marc Anthony threw to mark his 40th last year (08).

Organisers are working hard to keep the media guessing about the venue and guest list - but a number of A-list stars are expected to jet into the Big Apple to help the superstar welcome in her 40s, including Tom Cruise, Katie Holmes and Victoria Beckham.

The party is expected to include performances and dancers have been auditioned all week to take part in the extravaganza.

An insider tells WENN, "Everything is being kept top secret. Even performers won't be told if they have been hired until the last minute, to prevent details of the party from being leaked.

"Organisers are determined to keep the media away."