LONDON May 13, 2005 — Cameron Diaz is suing the British tabloid newspaper The Sun over a story suggesting she was having an affair with a married man.

Lawyer Simon Smith said the actress had instructed his firm, Schillings, to start libel proceedings against the publishers of The Sun. Smith said lawyers hoped to file a writ by Monday.

The Sun said it wouldn't comment until it had received legal papers.

On Thursday, The Sun carried a story claiming Diaz, who is dating singer Justin Timberlake, had a close relationship with a married television producer.

Schillings accused the newspaper of "falsely alleging that she had embarked upon a secret affair with a married man."

The firm is also representing Timberlake in a lawsuit against the News of the World tabloid over a story claiming he had cheated on Diaz.

Diaz, 32, starred in "There's Something About Mary" and the "Charlie's Angels" films. She is the voice of Princess Fiona in the "Shrek" animated ogre franchise.

Timberlake, 24, will provide the voice for a new character in "Shrek 3."