Ashton Kutcher took to Twitter on Wednesday to slam rumors that he cheated on wife Demi Moore.

“I think Star magazine calling me a “cheater” qualifies as defamation of character. I hope my lawyer agrees,” he wrote. “STAR magazine - you don’t get to stand behind “freedom of the press” when you are writing fiction.”

Star reported that an eyewitness saw Ashton “kissing and groping a hot young blonde by an out-of-the-way bathroom at Italian restaurant Madeo in L.A.”

“Ashton had this gorgeous girl pinned against the wall, and he was totally making out with her,” the source told Star. “I was shocked to see him sucking face with a girl who obviously wasn’t Demi.”

Ashton’s rep denied the story.

LAS VEGAS — Paris Hilton was banned Wednesday from two Wynn resorts on the Las Vegas Strip, and her boyfriend was dismissed as a nightclub partner following their arrests in a vehicle that police said reeked of marijuana.

Wynn Resorts Ltd. spokeswoman Jennifer Dunne told The Associated Press that Hilton is barred from Wynn Las Vegas and Encore.

Meanwhile, boyfriend Cy Waits was “separated” from his job after less than a week as top managing partner of the Tryst Nightclub at Wynn and XS The Nightclub at Encore, Dunne said in a statement.

Waits and a lawyer and publicist for the 29-year-old Hilton did not immediately respond to requests for comment.