Advance NZ has filed an urgent injunction against MediaWorks today after being excluded from the minor parties leaders' debate.

Co-leaders Billy Te Kahika and former National Party MP Jami-Lee Ross said in a statement the urgent interlocutory injunction application was filed in the High Court at Auckland.

The TV network will host the debate, aired this Saturday, with Act leader David Seymour, Green Party co-leader Marama Davidson and Māori Party co-leader John Tamihere.

Despite being excluded from MediaWorks' debate, Advance NZ will take part in TVNZ's minor party debate because of its criteria to include current sitting members of Parliament. Ross is Botany's MP but has said he has dropped out of the race for the electorate ahead of October 17 election.

In today's statement, Ross said MediaWorks' decision to exclude Advance NZ - which had 1 per cent of voter support in a recent 1 News-Colmar Brunton poll- will cause the party serious harm if left unchallenged.

"Seeking judicial intervention is no small step, but as one of the guardians of television coverage of the democratic process, MediaWorks' decision requires urgent review," he said.

"Advance NZ believes in the importance of New Zealanders hearing a range of opinions from political parties ahead of casting their ballot, and that parties should have fair access to major public platforms."

Advance NZ has been questioned for seemingly propagating internet conspiracy theories about Covid-19, the United Nations, and 5G among others.

Thousands of the party's followers have marched and rallied against Covid-19 restrictions and lockdowns this year.

"Advance NZ candidates have been excluded from a range of electoral political debates around the country, and it is time to stand up for the people and perspectives we represent," Ross said in the statement.

"This is not the first time that a political party has challenged a decision by a television network as to who is permitted to participate in a multi-party election debate."

Before the 2017 election, The Opportunities Party (TOP) filed an application for an urgent judicial review after TVNZ excluded its founder and then leader Gareth Morgan from its debates.

The High Court ruled against TOP and Morgan.

However, in 2014 then Conservative Party leader Colin Craig successfully challenged MediaWorks in court after not being invited to the minor parties' debate.

And in 2005, the High Court also ruled in favour of United Future leader Peter Dunne and Progressive Party leader Jim Anderton being added to TV3's leaders' debate.

Advance NZ said it has instructed Honor Lanham and Jordan Grimmer as counsel, who will be assisted by Wellington lawyer Graeme Edgeler.

Massey University communications professor Claire Robinson has also provided independent expert evidence to assist the court, the party said.