Sean Penn back with wife

Sean Penn and estranged wife Robin Wright Penn are reportedly back together.The Oscar-winning actor and the 'Forrest Gump' actress - who announced their separation last year - attended a party in Cannes, France, on Saturday night (17.05.08), which was hosted by model Petra Nemcova, who dated Sean after he initially split from Robin.An onlooker at the party on Nikki Beach said: "Surprisingly, there didn't appear to be any tension and they all sat and comfortably chatted."At one point during the evening, Sean left Robin to go and chat to Petra - who was hosting the bash to showcase her new documentary about the meaning of love - while Robin spoke to U2 frontman Bono.The source added: "Petra and Sean had a pretty long conversation, while Robin chatted with Bono. Once Petra made her announcement about the documentary, Sean and Robin were back together." Sean and Robin called off their divorce in April, after applying to a San Francisco judge to stop the divorce proceedings during a hearing.In a one-page document filed in Marin County Superior Court, the clerk dismissed the couple's petition at their request.

Robin, 43, filed for divorce on December 21 citing irreconcilable differences.

The couple met on the set of the 1990 thriller 'State of Grace' and married in 1996.

They have two teenage children, daughter Dylan Frances and son Hopper Jack.