Donald Trump has responded to calls for a pardon for Joe Exotic, the colourful zoo owner at the centre of Netflix's breakout hit Tiger King.

Exotic - whose real name is Joseph Maldonado-Passage - is a mulleted, gun-toting polygamist and country-western singer who bred exotic animals while running an Oklahoma zoo.

He is serving 22 years in prison for plotting to have an animal rights activist murdered.

However, fans of documentary series Tiger King: Murder, Mayhem And Madness believe he is innocent and Donald Trump Jr, the president's son, joked he should be pardoned.

Mr Trump was asked about Exotic's case during a press conference on Wednesday.

"I know nothing about it," a smiling Mr Trump replied. "He has 22 years for what - what did he do?"