Former minister James Shaw will give his departing speech to Parliament this week and is reflecting on the tougher moments of his time in office.

He admitted he came close to throwing in the towel several times when he met resistance to climate change reform.

Shaw resigned from his role as the Green Party co-leader in January after nearly nine years in the job.

He served as the previous government’s climate change minister for six years before being appointed associate environment minister in Labour’s second term, where he oversaw biodiversity.

Shaw previously declined to answer questions during previous interviews about whether he had ever threatened to quit while serving as a minister. Shaw expressed his public frustration with the pace of advancement with his coalition partner while serving as co-leader.

However, as he prepares to give his departing speech this week, he was candid with Jack Tame on TVNZ’s Q&A.

He said there were times when he was “really close” to calling it quits.

“There were a few times, the two most significant ones would’ve been, when we were debating increasing our Paris [the 2030] target, prior to the Glasgow conference,” Shaw said.

“The other one was the National Policy Statement on Indigenous Biodiversity, which is currently getting unwound.

“But that got really difficult, and I ended up storming out of the Cabinet meeting that decided it. Three minutes later, David Parker materialised in my office to say, ‘look, we’re gonna work out a way to get this done’.”

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He said he told minister Megan Woods his resignation letter was written out and he would hand it in if it went through.

“That programme, indigenous biodiversity, something in absolute crisis. We’d gone 30 years without national direction on it - there had been a number of attempts.”

Former Greens co-leader James Shaw said he came close to quitting during his career. Photo / Mark Mitchell

Shaw was a major force behind the previous government’s climate change policies while serving as minister.

Shaw told Q&A that he thought the Zero Carbon Act had passed its “first acid test” by withstanding the change in administration.

Act promised during the election campaign to repeal the law. Shaw did, however, express confidence that the National Party was dedicated to maintaining it.

The former co-leader acknowledged that he was unable to force through all of the legislative measures he wanted, including the pricing of agricultural emissions.

“First of all, I think we’ve got the way we organised ourselves, wrong. We needed single-point accountability inside the government,” Shaw said.

“We should probably have parked the work with the Treasury, rather than with the Ministry for Primary Industries and the Ministry for the Environment, because the kind of tensions between those agencies was a big part of the problem.”

This article was originally posted on the NZ Herald here.