BERLIN • A politically charged Berlin film festival opened on Thursday with a French movie about the Nazis' persecution of gypsy-jazz great Django Reinhardt and a vow by Hollywood's Maggie Gyllenhaal that Americans were "ready to resist" United States President Donald Trump.

Eighteen movies are vying for the festival's Golden Bear top prize, to be awarded on Feb 18 by a jury led by director Paul Verhoeven (Basic Instinct, 1992).

Living up to the Berlinale's reputation as the most topical of the big festivals, the jury wasted no time in taking aim at Mr Trump who has drawn fierce criticism from the art world, particularly over his disputed travel ban.

"I want people to know there are many, many people in my country who are ready to resist," jury member Gyllenhaal, 39, told reporters.

Mexican director and actor Diego Luna, 37, used humour to criticise Mr Trump's plan to build a wall along the border with Mexico.

"I'm here to investigate how to tear down walls," he quipped, in a nod to Berlin's decades-long division.

The Berlinale's kick-off film Django takes viewers back to occupied France in 1943 and the life of Reinhardt, who refuses to take part in a tour of Germany that the Nazis want to use to divert attention from American "negro" jazz.

Reinhardt, his elderly mother and his pregnant wife became refugees. However he was arrested by German troops, briefly imprisoned and forced to perform.

Director Etienne Comar said he took some liberties with the actual story, but that its essence was true to history and the Catch-22 faced by artists under repressive regimes.

"It is the question: Do you raise your voice by continuing to play music, writing music that expresses your resistance?" he said, noting the lengthy archival work he had done to present an accurate portrait.

The film stars Reda Kateb, who appeared with Viggo Mortensen in the Algeria-set war drama Far From Men (2015).

AGENCE FRANCE-PRESSE