Tom Cruise is giving his pregnant fiancée Katie Holmes an incredible $20 million wedding present — her own jet plane!

In one of the most outrageously expensive gestures of love in Hollywood history, sources say the War Of The Worlds star has ordered a customized Gulfstream for the Dawson's Creek cutie.

"Forget diamond rings," said the insider. "Tom's decided on the ultimate wedding gift — Katie's own executive jet complete with pilot and crew at the ready.

"Tom wanted to come up with the most amazing wedding gift ever, something that would make her life so much better than a big diamond rock on her finger. And, boy, did he!"

We can reveal that Tom, 43, and Katie, 26, had planned to wed in Cancun, Mexico, in late October, but they were forced to postpone the nuptials because of Hurricane Wilma. Now they are trying to fit a walk down the aisle into Tom's busy shooting schedule for Mission: Impossible III.

Family and friends have been told they may get just two days' notice of a wedding — hopefully before the end of the year.

According to the insider, Tom — who has just headed off to Shanghai for work on the movie — is buying the jet because he wants Katie and her entourage to be able to travel in comfort and style when she visits him on location or her parents in Ohio.