The stars have always been known to come forward for a good cause. Gulzar, Farhan Akhtar and Abhay Deol have been tagged 'green hearts' after they signed up for British aid agency Oxfam India's message on climate change. The event happened at the 11th annual Osian's Cinefan film festival of Asian and Arab cinema. They will be speaking and expressing their concern over the climate change in the world.