Conservative Party leader Colin Craig is pressing ahead with his threat to sue Green Party co-leader Russel Norman, the Greens say.
A Conservative Party spokeswoman confirmed the action was proceeding but said there would be no further comment.
The Greens said papers were filed in the Wellington District Court.
Green Party spokesman Andrew Campbell said, in a statement today, the party would defend the case "because we believe in freedom of political speech and an inclusive and tolerant society".
"This case is a diversion from the issues that really matter to New Zealanders.
"This year's election should be about debating the real issues, such as people struggling to pay their power bills and facing mortgage hikes and increased costs - the Green Party will continue to work to make New Zealand a smart, greener, more compassionate place to live," Campbell said.
"Colin Craig may want to spend his time arguing in court, but the Green Party will continue to focus its energy on the issues that are important to everyday New Zealanders."
Craig wrote to the Greens last week with a deadline of last Friday for Norman to apologise for comments he made suggesting the Conservative Party leader was sexist and homophobic.
Craig is demanding a retraction and apology from Norman over comments he made at Auckland's Big Gay Out.
Norman said at the event that Craig thought a woman's place was in the kitchen and a gay man's was in the closet. Norman has already refused to resile from his comments, calling Craig's views "offensive".
- Fairfax Media
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