Lesbian romance 'Blue Is The Warmest Colour' has scooped the coveted Palme d'Or prize at the Cannes Film Festival.

The French film, 'La Vie d'Adele - Chapitre 1 & 2 (Blue Is The Warmest Colour)', was the critics' early favourite, and made history by being the first winner to depict a same-sex relationship featuring long, graphic love scenes.

The esteemed judging panel - which includes Steven Spielberg, Nicole Kidman and 'Life of Pi' director Ang Lee - made the unusual decision to award the top prize not just to Tunisian-born director Abdellatif Kechiche, but also to the film's two stars, Adele Exarchopoulos and Lea Seydoux.

Spielberg explained: ''The film is a great love story that made all of us feel privileged to be a fly on the wall, to see this story of deep love and deep heartbreak evolve from the beginning.

''The director didn't put any constraints on the narrative, on the storytelling. He let the scenes play as long as scenes play in real life.''

The film is a heartbreaking coming of age story about a schoolgirl (Exarchopoulos) who falls for an older woman (Seydoux).

The landmark win comes mere days after France legalised gay marriage, while protests were simultaneously occurring against the new law in Paris.

However, Cristian Mungiu, Romanian director and jury member, insisted: ''We were giving awards to cinema, not for political statements.''

The Coen Brothers' 1960s inspired film 'Inside Llewyn Davis' earned the Grand Prix, the second most prestigious award, with third place going to Japanese director Kore-Eda Hirokazu's 'S'oshite Chichi Ni Naru (Like Father, Like Son)'.

Best actor went to Bruce Dern thanks to his performance as an alcoholic, aging father on a road trip with his son in Alexander Payne's 'Nebraska' and Berenice Bejo took the best actress prize for 'Le Passe (The Past)'.