The Green Party says there's no contradiction in campaigning for donation transparency while calling for contributions to match an unnamed donor.

Photo: RNZ / Rebekah Parsons-King

The party sent out an email in co-leader James Shaw's name, requesting donations big and small, as someone has offered to match donations dollar-for-dollar up to $25,000.

The email describes the donor as a 'champion' whose potential contribution will give the party a boost it desperately needs to hire a world-class campaign director for the 2020 election.

A spokesperson won't reveal who the mystery donor was, but said they're a long-term supporter of the party.

"The identity of the donor will be disclosed according to electoral law, i.e. in the annual return if the donation exceeds $15,000 which is likely as part of this appeal.

"We run these sort of matching appeals from time to time with members; it's the first time one has been emailed out so widely to supporters.

"This appeal is to support the funding for a professional election campaign director and occurs regularly every three years in the build-up to an election. It is traditionally one of our best performing appeals", they said.

The donation drive comes as the Greens push for more transparency around political donations.

However, a spokesperson said they're operating within the current rules.

"We don't see any contradiction in calling for those rules to change for all parties so that big money can be kept out of politics, including an annual cap of $35,000 on donations from any individual.

"In the meantime, we also apply our own internal major donors policy, which sets rules on who we will accept donations from, which has led to some donations being turned down in the past," they said.