Charlize Theron vacations with Sean Penn

Actress Charlize Theron has sparked rumors of a new romance with Sean Penn by vacationing with her fellow Oscar winner in Hawaii and ringing in the new year (14) with him.

The Monster star was photographed relaxing on a beach with Penn earlier this week (begs30Dec13). They also enjoyed a little surfing near the 53 year old's holiday home, where a witness tells the New York Daily News the pair looked "very close and comfortable together".

They further fueled dating speculation on Wednesday (01Jan14) when they arrived back in Los Angeles on the same plane, although they avoided being snapped together and departed separately.

Theron, who was not joined by her baby son Jackson for the beach break, was most recently linked to Family Guy creator Seth MacFarlane, while Penn, who was previously married to Madonna and newly-engaged actress Robin Wright, has also dated Scarlett Johansson.