About 10 members of the anti-Islam, anti-immigration group wore what appeared to be fancy dress Arabic attire, including a bright pink burqa and a metallic gold floor length robe, as they "stormed" Gosford Anglican Church on Sunday.

Father Rod Bower was halfway through his sermon when the intruders entered the church, performing mock prayers and blaring a recording of a Koran recitation.

Footage of the stunt was posted on Facebook, where an image of One Nation leader Pauline Hanson smiles from the Party for Freedom's profile picture.

The tagline on the party's official website appropriates Donald Trump's campaign slogan: Make Australia Great Again.

The group posted several videos of "Operation Rod: Patriots Storm Church of Apostasy".

In each clip the group spouts the same hard-right rhetoric that it has used at a spate of demonstrations in Sydney and Melbourne in recent months.

Party for Freedom gained national attention when its chairman Nick Folkes was one of four men who disrupted a memorial for Lindt cafe siege victims in Martin Place in December 2014.

The group bore signs proclaiming: "Muslim terrorists not wanted here - neither are their leftist supporters", "Tony Abbott - Will you protect us from multiculturalism?" and "We didn't start the fire!"

Sharing its name with Geert Wilders' hard-right populist, nationalist party in the Netherlands, Australia's Party for Freedom sprang from the now defunct Australian Protectionist Party that courted the xenophobic vote in the 2012 council elections.

Folkes, an industrial painter, wanted Leichhardt council declared a "sharia-free zone" and wanted to scrap council grants to multicultural groups.

But the party, which calls for an end to Muslim immigration and multiculturalism, has more recently thrown its support behind Hanson and One Nation.

"Pauline Hanson has been consistent for the past twenty years with her views on immigration, foreign ownership, employment, youth and aboriginal issues, political correctness and more recently Islam," a post by the group on its Facebook page reads.

"Pauline's political re-emergence has been the greatest development in Australian politics in the past twenty odd years," the post reads.

It invites supporters to join the group's "Welcome Back Pauline Party" when Parliament resumes.

The group's website also invited supporters to join its "Trump Patriots" family barbecue in Penrith in July, celebrating the US presidential hopeful's plans to stop Muslim immigration and build a wall to end undocumented arrivals through Mexico.

Folkes was among roughly 100 demonstrators outside the ABC's headquarters in Ultimo during Hanson's appearance on the broadcaster's Q&A program in July.

The anti-immigration contingent held signs including "Welcome back Pauline" and "Multiculturalism has utterly failed".

In April, Folkes said he had organised a protest at the Halal food festival in Melbourne that erupted into a violent brawl when a small group of anti-Islam protesters clashed with anti-racism activists, leaving one man bleeding from a head wound.

The right-wing activists wore T-shirts that read "Rapefugees … not welcome, stay away" and waved placards reading "Muslim terrorists not welcome here".

Folkes planned to commemorate the 10-year anniversary of the 2005 Cronulla riots last December, but was hauled before the NSW Supreme Court as the NSW Police Commissioner tried to stop the rally.

The Gosford stunt was not the first time the Party for Freedom has worn Muslim dress to mock the religion.

Folkes donned what he called "Islamic garb" for his court appearance when he defended the "peaceful assembly" to commemorate the Cronulla riots.

His bid to hold the rally was blocked by a court order and instead, he held a commemorative barbecue on the beach.

But the barbecue was a fizzer for the party, with its supporters being outnumbered by reporters and anti-racism protesters.

Folkes confirmed to Fairfax Media that he was among those in the church on Sunday.

"We are not affiliated with One Nation but I do support Pauline Hanson," he said.

"We held the protest to challenge [Father Bower's] promotion of Islam and Muslim immigration."

Father Bower said the rise of the One Nation Leader, whose party has snared four Senate spots, was "symptomatic of a group of people feeling marginalised".

"Pauline Hanson is a very clever manipulator of those people and … will exacerbate their fear," he said.

The incident follows reports that several senators, including those from One Nation, want to strike section 18C from the Racial Discrimination Act.

The section makes it unlawful to publicly "offend, insult, humiliate or intimidate another person or a group of people" on the basis of race. Opponents say the measure restricts freedom of speech.

Father Bower said the incident at his church "highlights the need for 18C".

"If you lose 18C then this kind of vilification and abusive behaviour will go even more unchecked," he said.

One Nation has been contacted for comment.

Fairfax Media