Six siblings of a Republican congressman in the US have appeared in a campaign video supporting his Democratic rival.

Paul Gosar is seeking re-election in Arizona in the November mid-term elections, after securing a fourth term in 2016 with more than 70% of the vote.

He has, however, proven a controversial figure - making headlines for voicing support for the British far-right figure Tommy Robinson, and repeating a false conspiracy theory that the violence in Charlottesville last year was a 'left-wing plot'.

He is also a strong supporter of Donald Trump, and a proponent of stricter immigration laws.

Mr Gosar is up against Democrat David Brill in the upcoming election.

Now, six of the Republican's nine siblings have endorsed his rival.

David, Gaston, Grace, Jennifer, Joan and Tim Gosar have all appeared in a series of campaign videos for Dr Brill.

Grace said: "Paul Gosar the congressman isn't doing anything to help rural America."

Her sister Jennifer added: "If he actually cared about people in rural Arizona, I bet he'd be fighting for social security, for better access to healthcare.

"It's horrible to have to do this... this isn't just about Paul, it's about the family."

Tim Gosar argued: "It's intervention time - and intervention time means you go to vote, and you go to vote Paul out."

It's not the first time the Gosar siblings have spoken out against their brother.

In a letter last year after the congressman's comments about billionaire George Soros (who funds a number of high-profile progressive causes), seven Gosars wrote: "We are aghast that Paul has sunk so low that he now spews the most despicable slander against an 87-year-old man without a shred of proof, and then doesn’t even have the guts or decency to apologise?"