Sean Penn traded an autograph for cigarettes.

The 'Gangster Squad' star was out with his new girlfriend Charlize Theron jogging, but when he got back to their car he suddenly realised he'd left his packed at home.

A source said: ''He asked Charlize if she'd brought her smokes, but she hadn't. and because he'd left his wallet at her house, he couldn't buy a new pack.''

Sean, 53, was then approached by a fan who happened to have a packet of cigarettes protruding from his front pocket, prompting a change of heart in Sean, who never normally poses for pictures with people.

When the fan asked if he could have a photo the actor retorted: ''How about I trade you a photograph for a couple of cigs?'', according to the National Enquirer.

The man was happy to hand over his whole packet, but Sean didn't want to take advantage and reportedly just took two, and happily posed for a photo.