Sean Penn has declared that Charlize Theron is the love of his life.

The 54-year-old Gangster Squad star was quick to correct a journalist from French newspaper Le Parisien when they referred to the 39-year-old actress as his girlfriend.

Penn said: "'No, no, excuse me, Charlize is not my girlfriend. She's the love of my life...

''We have a very strong relationship. [We] have known each other for a very long time. But we weren't together.''

Speaking previously, Penn admitted that despite being married twice before (to Madonna for four years and Robin Wright for 14 years), if he was to marry Theron he would consider it his first marriage. 

He explained: ''You say I've been married twice before but I've been married under circumstances where I was less informed than I am today, so I wouldn't even consider a third marriage, I'd consider it a first marriage on its own terms if I got married again. I mean, I like the tradition.''