A former Greens MP has given James Shaw a ringing endorsement as he fights to retain his role as co-leader of the party.
Shaw faces a potential leadership challenge after more than 25 percent of party delegates at an annual meeting last weekend voted to reopen nominations for the co-leadership role.
But Shaw has received an endorsement from former Greens MP Kevin Hague, who was with the party from 2008 to 2016.
Hague came second to Shaw in a leadership contest in 2015 after former Greens co-leader Russel Norman vacated the role.
Hague told Newshub Nation on Saturday Shaw has been key in leading the Greens back into Government.
"You know, some people might be surprised to hear me say it but I think James absolutely is the right person to be the leader, and he has my support," Hague told host Simon Shepherd.
"I think he's actually done a really good job of taking the party into Government and achieving things while in Government. I think he's been a good minister."
Some of the complaints by fellow Greens delegates suggested the Climate Change Minister hadn't fought strongly enough for Green values and that he was becoming a lapdog of Labour.
But Hague said Shaw had achieved some "really difficult things" when it came to climate change.
"He's been able to achieve some things that are really difficult to achieve, such as the consensus of parties around climate change and establishing the Climate Change Commission," Hague said.
"That's really necessary architecture for the kind of climate response that we need to make as a country and it's really James, who deserves the credit for that.
"He has actually achieved more as minister than every previous minister, every previous Government put together before him."
Hague doesn't believe a faction of the Greens is out to get Shaw, rather it's just a disagreement within the party.
"I think there is a disagreement going on here and disagreements are normal human things and the Green Party has a culture of being able to resolve disagreements in a healthy way," he said.
"That's really what should be going on here. They have as one of their core principles, good decision making and that means that when the Greens set out to make a decision, they try and do so by consensus."
Shaw said he will run for the co-leader role again but so far has no challengers against him.
Elizabeth Kerekere and Chlöe Swarbrick ruled themselves out earlier this week while Teanau Tuiono said he's "not ruling anything in, I'm not ruling anything out".
Hague told Newshub Nation he was "disappointed" with how the Greens have handled things.
"I'm certainly disappointed that concerns were raised in this way, this is not the kind of healthy way I would expect to see disagreements aired in the Greens."
The former Greens MP doesn't believe Shaw has been tainted by losing his co-leadership role.
ACT Party leader David Seymour also praised Shaw earlier this week, saying the Greens would be "mad" to dump him.
"I know a lot of people who will find this hard to believe but he's the sanest amongst them by far," he told AM Early host Bernadine Oliver-Kerby on Thursday.
"It's just such a shame that the Green Party's immune system has been rejecting James Shaw."
The Greens and Labour have a cooperation agreement that outlines the ministerial posts held by Shaw and co-leader Marama Davidson, as well as the areas the two parties agree to work together on.
After Shaw was deposed of the co-leadership, Prime Minister Jacinda Ardern confirmed he would remain Climate Change Minister regardless of whether he was co-leader or not. She said the cooperation agreement specifically names Shaw as the minister, rather than saying the co-leader is the minister.
Watch the full interview with Kevin Hague above.
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