Natalie Portman is not dating Sean Penn.

The 'Garden State' actress broke her rule of not speaking to the media about gossip to dismiss the rumours linking her to the 'Milk' star.

Penn (48) and his wife Robin Wright Penn recently separated with press reports now claiming that he and Portman have since become an item.

"Sean Penn is a friend and colleague," the 27-year-old actress said in a statement issued to US TV show 'Extra'.

"The reports that we are romantically involved are completely untrue," she insisted.

"I normally do not respond to rumours about my private life, however, this repeatedly fabricated story has forced me to do so."

Portman has previously been linked romantically with actors Jake Gyllenhaal and Gael García Bernal and most recently musician Devendra Banhart.