Michael Moore has premiered a surprise film discussing the US presidential election just three weeks before Americans head to the polls.

Moore debuted Michael Moore In TrumpLand in New York on Tuesday night in front of an audience of his fans.

The film features Moore speaking about both Republican nominee Donald Trump and Democratic candidate Hillary Clinton on stage earlier this month in Wilmington, Ohio, a hotbed of Trump support, according to The Hollywood Reporter.

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The liberal documentary maker urged the crowd at Tuesday's premiere to vote for Mrs Clinton next month.

The film will screen for one week at the IFC Centre in Manhattan beginning on Wednesday and will also be shown at a cinema in Encino, California, The Hollywood Reporter said.

Moore said he hopes more cinemas will be announced soon.