But the Concerned Citizens of Canberra has defended the appointments, saying a Gungahlin mosque has a national, not just local, significance.

The vocal group has waged a legal battle to stop the construction of the 500-capacity mosque in Gungahlin since planning authorities approved it in August 2012.

Concerned Citizens is mounting an ACT Supreme Court appeal against the development after its challenge on planning grounds - including "social impact", "public interest" and concerns about traffic and noise - was dismissed in July.

Concerned Citizens is headed by Canberra couple Irwin and Jill Ross, who hold the positions of president and secretary. The couple reside in West Belconnen, about 15 kilometres from the proposed site.

But documents, lodged with the ACT Office of Regulatory Services, reveal the Rosses are the only two territory residents listed on the Concerned Citizens executive.

The documents show Southern Highland residents Adrian Van Der Byl, of Tallong, and Max Cracknell, of Tahmoor, also hold board positions.

Documents said Mr Van Der Byl recently replaced Canberra's Adrian Adair as vice-president, while Mr Cracknell is listed as treasurer.

But Mr Ross defended the interstate appointments, claiming the construction of the religious buildings in Gungahlin was a national issue, as home-grown Islamic extremists had links to Australian mosques.

"Wherever a mosque goes up … it affects the whole area. It concerns the whole of Australia," Mr Ross said.

"Is a mosque just a place of worship, like a church or synagogue?"

Mr Ross said Concerned Citizens had both local and interstate members.

"We have supporters in Canberra and out of Canberra," he said.

"I'm not saying who is from where or how many, but we have supporters and there's supporters all over the place."

Both Mr Cracknell and Mr Van Der Byl have previously run as candidates for Fred Nile's Christian Democratic Party at either state and federal elections.

Mr Van Der Byl - who said he opposed "the advancing Islamisation of Australia" - confirmed he planned to run as the CDP candidate in the seat of Goulburn, which borders the north of the ACT, at the coming NSW state election.

Mr Cracknell - who was also involved in the fight against an Islamic school in Camden, in Sydney's west - lives about 205 kilometres from Canberra.

It is understood Mr Cracknell is also president of the anti-Islamic Australian Christian Nation Association.

The association's web page said the group had been established to "promote the Christian foundations of Australia (New South Wales) and for it to continue as a predominantly Christian nation".

He declined to comment when contacted by Fairfax Media.

Mr Van Der Byl – who lives about 125 kilometres from Gungahlin – said he did not think his geographic separation from the capital precluded his involvement in the vocal anti-Mosque group.

He said he had the right to be hold the position due to his intention to run as the CDP candidate for Goulburn

"[Canberra] is not that far away from my geographical interests … [so] I have a considerable interest in it and the anti-mosque movement as a whole," he said.

"I'm interested in the social impact it will have on Canberra, as well as the state seat of Goulburn, which butts right up next to it."

Mr Van Der Byl said he was also involved in other concerned citizen groups around Australia, including membership of the Marulan Action Group, which opposes a proposed mosque and Islamic cemetery in the Southern Highlands.

He said he was part of a clique of people who opposed the "the advancing Islamisation of Australia".

"There are many thousands of people throughout Australia spending lots of time, effort and money fighting the establishment of mosques," he said.

"The whole issue is a federal issue … it affects our constitution, which few people realise.

"It is being used for the practice and furtherance of Islam, which is, in effect, a parallel civilisation with its own civil laws designed specifically for the destruction of its host nation."