The movie's backers showed 10 minutes of out-takes from the picture to market buyers and reporters on the sidelines of the festival's sprawling European Film Market.

The scenes bear more than a passing resemblance to the Oscar-nominated 2004 German film "Downfall" starring Bruno Ganz, but juxtapose the story against Mahatma Gandhi's non-violent struggle for Indian independence from the British.

The Fuehrer, as played by veteran Indian actor Raghubir Yadav, sports the trademark truncated moustache and harangues his generals deep in his Berlin bunker, albeit in clipped Hindi.

Former Miss India Neha Dhupia portrays Eva Braun, whom Hitler married hours before they committed suicide in the bunker in April 1945.

The title alludes to two letters Gandhi wrote in which he appealed to the Nazi dictator in the vain hope of stopping the war.

Even before its premiere, the film has drawn opposition from sections of India's small Jewish community and campaigners abroad for what they feared would be a trivialised portrayal of the fascist leader.

But producer Anil Sharma defended the theme of the movie, which is a rare foray into dark material for the Bollywood film industry, more famous for its vast and colourful dance routines and suggestive love scenes.

"We are not glorifying any character," he told AFP. "We are just telling a lost chapter of Indian independence history."

Sharma said that the title had generated intense "curiosity" among international buyers in the German capital.

"We have just finished the production of the film and we came to this festival to show it for the first time," he said.

"We are negotiating with a lot of buyers and exploring possibilities," he added, declining to go into specifics.

The film contrasts the fall of the Third Reich with Gandhi's vision for a bloodless struggle that would free India from the British, which Sharma called the ideological clash between "world peace and world turmoil".

The original lead actor, Bollywood star Anupam Kher, pulled out of the production early on in the face of protests.

"I am deeply moved by the outpouring of messages on social networks, the letters which I have received and the protestations I have heard about from organisations in many countries," he said in a statement sent to AFP last June.

He added on his Twitter account that "sometimes human emotions are more important than cinema."

However Sharma insisted Kher had simply been wrong for the part and was replaced with Yadav.

Hollywood and European film makers have made dozens of films on Hitler, but opposition to the Bollywood production appears to stem partly from a belief that "Dear Friend Hitler" will misrepresent or make light of the Holocaust.

The film, which cost about three million dollars to make, was shot in studio and on location in India.