London, Sept 5 : Cheryl Cole and Cameron Diaz have become close friends while filming their upcoming movie `What To Expect When You're Expecting'.

The 28-year-old singer was drafted on to the film as a talent show judge who watches a performance by the 39-year-old American actress' character.

The two have become bosom buddies after hanging out on the sets of the flick and have been organising a trip to New York since the singer has arrived home.

"Cheryl has a dirty sense of humour and Cameron found her funny. They've been planning a girly weekend if they can find a spot in their diaries," the Sun quoted a source as saying. (ANI)