07/27/2004 at 10:00 AM EDT
Making good on his threat, Justin Timberlake has filed a libel suit against the British tabloid News of the World, after the publication claimed in a story that he was unfaithful to girlfriend Cameron Diaz.
Lawyers from the British firm of Schillings initiated the suit on Timberlake's behalf after the News of the World refused the singer's request for damages and a retraction.
The firm's Simon Smith tells BBC News that the legal action will be pursued with "some vigor," while a New of the World spokeswoman countered by saying the paper stands by its story and "will vigorously defend these proceedings in court."
As Timberlake told TV's Access Hollywood about taking legal action: "Any time it goes to a certain level where I just feel uncomfortable with it, I think it's necessary. ... It's really about principle."
The 23-year-old pop star and the 31-year-old actress have been together for nearly a year, but on July 18, the News of the World ran a story in which model Lucy Clarkson – best-known in her native Britain for her impersonation of Tomb Raider character Lara Croft in a computer game – said she spent two "sizzling nights" with Timberlake while he was in London and Diaz was in Los Angeles.
After the tabloid story surfaced, Diaz was quoted as saying: "I trust Justin. This woman just wants her moment in the spotlight."
Timberlake's West Coast attorney, Martin Singer, told TV's Celebrity Justice last week that the News of the World story was untrue and that he was drafting letters to the tabloid demanding money, an apology and a retraction.