EMBATTLED heiress Paris Hilton is standing up David Letterman.

Late yesterday,Hilton canceled what had been scheduled to be her first interview since sexually explicit tapes of her were leaked to media outlets and made their way onto the Internet. “Late Show” staffers seemed to be the last to find out she was pulling out. Representatives of the show had spent the morning publicizing her upcoming appearance – only to have Paris pull the rug out late yesterday afternoon.

“We have not received word that her booking is canceled,” a Letterman spokeswoman said last night. Hilton had been booked to appear on the show next Wednesday to promote her upcoming reality show,”The Simple Life .” The arrangements were made weeks ago, before the tape controversy. “The Simple Life “is a send-up of the classic TV show “Green Acres .”But in this version,Hilton,22, and socialite friend Nicole Ritchie (daughter of singer Lionel Ritchie)are sent to live and work on a farm.