Pop star Ashlee Simpson has slammed Nick Carter's claims they slept together while the Backstreet Boy was still dating socialite Paris Hilron. Carter told PageSix.com on Sunday (01OCT06) that he had a brief affair with Simpson after he heard rumours Hilton was cheating on him with her House of Wax co-star Chad Michael Murray on set in Australia. The I Want It That Way hitmaker and Hilton dated for eight months before splitting in July 2004 - the same month Murray announced his engagement to his One Tree Hill co-star Sophia Bush after proposing Down Under. Carter said, "I hooked up with Ashlee Simpson. When Paris came back from Australia, they talked to each other and she found out about it." However, Simpson insists the alleged tryst never took place, telling MSN, "No! That is so random. When I heard that, I was dying laughing."