Oscar-winning film-maker Martin McDonagh has said he “definitely wasn’t aware” that Australia’s official no campaign was using a scene from his film Seven Psychopaths in the lead-up to the Indigenous voice referendum, alleging it “appears to be deliberate copyright infringement by a bunch of rightwing swine”.

McDonagh told Guardian Australia on Friday he had “contacted my agents and producer to have them desist”.

On Thursday, the no campaign group Fair Australia shared a short scene from the 2012 film Seven Psychopaths on Twitter and Instagram, with the face of the prime minister, Anthony Albanese, superimposed over Zeljko Ivanek, who in the film plays a thug who threatens the character Hans (Christopher Walken) with a gun.

Walken’s face has an Australian flag imposed on it while Albanese is wearing a yes campaign badge.

When Hans doesn’t submit, the thug/Albanese is incredulous: “But I’ve got a gun. It doesn’t make any sense.”

“I don’t care,” Hans/Australia replies. “Too bad.”

Fair Australia is campaigning against the Indigenous voice to parliament. It is a project of conservative lobby group Advance, with Coalition senator Jacinta Nampijinpa Price as its spokesperson.

Fair Australia is the leading group campaigning against the referendum to be held on 14 October, which proposes to enshrine an advisory committee for Aboriginal and Torres Strait Islander people in the Australian constitution.

The voice would be a representative committee of Indigenous people providing advice to the federal government on policies affecting them.

The referendum is supported by the national Labor government but opposed by many members of the Coalition opposition, made up of the Liberal and National parties. It is also supported by the leaders of all Australian states and territories and a number of Liberals who disagree with their party’s position.

The clip was shared by Fair Australia on Twitter, Instagram and TikTok with the text: “Don’t let the elites bully you! Vote NO to Division!”

McDonagh – who also directed and wrote In Bruges, Three Billboards Outside Ebbing, Missouri, The Banshees of Inisherin and Oscar-winning 2016 short Six Shooter – said in his statement he was “obviously dead set against” the Seven Psychopaths clip being used.

The British-Irish film-maker added that he was moving to have them remove the clip: “Whether this will happen in time to help I do not know but I firmly stand with the First Nations on this matter.”

Fair Australia was contacted for comment and later tweeted: “Don’t know how it works in Hollywood, but in Australia there’s a thing called ‘parody’.”

Albanese’s office was also contacted.

“This is more of the same from the no campaign, same fear, same negativity,” a government source said.

“No hope, no vision, no belief we can come together for a better future. When the no campaign’s confusion and misdirection doesn’t deter people, they opt for negativity and vitriol.”

This week, another leading no campaigner, Warren Mundine, was critical of “division” and “abuse” in the referendum. He claimed, without citing specific examples, that Albanese had “attacked people who had a different opinion” and alleged the prime minister’s rhetoric had unleashed “horrible racial abuse”.

Albanese responded on Thursday by stating: “I’ve called him nothing, at any time. I think people will make their own judgment about who’s making attacks.”

Indigenous leader and yes campaigner Noel Pearson has called for voice supporters to “maintain the love”. He was responding to former Liberal prime minister John Howard’s call for no campaigners to “maintain the rage”.

“I was surprised that any eminent leader of the country would urge rage. I only say in response to it that, well, the no campaign might be inciting rage; we’re gonna incite love and faith and the removal of fear,” Pearson said on Thursday.