Hone Harawira plans to force a by-election in his Northland Te Tai Tokerau seat before the general election.
At the launch of his new Mana Party today he vowed to have a by-election held within six weeks.
Up to 300 people gathered at Mahurehure Marae for the Mana Party launch in Auckland today.
Sue Bradford lent her support but made no mention of whether she would stand as a candidate.
Bradford described the break-away party as a "party of activists" that has the support of unionists and political activists.
"We need a party that can really lead a fight and wouldn't just fiddle around the edge or cozy up to the Government for crumbs," the former Green MP said during her speech.
"There's only one way to ensure our rights and future and that's to fight for them.''
Political activist John Minto also aligned himself with the Mana Party.
"The Maori Party melted into the warm embrace of the National Party while Hone stayed strong," he said.
Political activists, socialists and former Green Party members are among those gathered at the Mana Party launch.
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