Political party leaders Jacinda Ardern, Winston Peters, David Seymour and James Shaw farewell Todd Muller

Todd Muller has resigned from the National Party's helm and fellow political party leaders are bidding him farewell with anecdotes about the pressures of leadership. 

Muller announced his resignation at 7:30am on Tuesday morning after less than two months in the role, following a weekend he described as reflecting on his experience as National leader over the last several weeks. 

"It has become clear to me that I am not the best person to be leader of the Opposition and leader of the New Zealand National Party at this critical time for New Zealand," he said in a press statement. 

Watch the Newshub Special on the National Party leadership crisis live tonight from 7:30pm on Newshub.co.nz.

"The role has taken a heavy toll on me personally, and on my family, and this has become untenable from a health perspective. For that reason I will be stepping down as leader effective immediately."

Muller asked for privacy and said he intends to spend some time out of the spotlight to spend with family and restore his energy before reconnecting with his community. 

Labour leader Jacinda Ardern

Prime Minister and Labour leader Jacinda Ardern passed on her best wishes to Muller's family. 

"I have just heard the news about the resignation of Mr Muller as leader of the National Party," she said on Tuesday morning. "No matter what side of Parliament you're sitting, politics is a difficult place. I have passed on my best wishes to Mr Muller and his family."

NZ First leader Winston Peters 

New Zealand First leader Winston Peters acknowledged the "heavy price" of trying to lead National - but he also took a crack at the party's "incompetent caucus". 

"One's sympathy goes out to Todd Muller and his family. Todd is a good man, unlike most of his colleagues he does have commercial experience, and he will bounce back," Peters said.

"Leading a divided and incompetent caucus would have tested even the best leader. The National caucus now has the unenviable job of selecting its fourth leader since the Coalition Government took office.

"The National caucus, like too many parties in Parliament, lacks business experience, life experience and political experience. Heaven only knows who will be the next cab off the ranks selected to lead such a dispirited and incompetent lot."

Peters said Muller "never had a chance" given the "fault lines of ambition, personality, and ideology that run deep" through the National Party caucus.

"National has demonstrated to voters as clearly as it is able that it cannot govern itself."

ACT leader David Seymour

ACT Party leader David Seymour described Muller as a "really nice guy" whose political experience was "in the warm bosom of the National Party heartland". 

He said being a leader is a "much more competitive environment" and admires Muller for "having the self-honesty and the honesty with those around him to recognise it wasn't working". 

He said Muller deserves respect for that. 

"It's a very competitive and bruising game and I just admire him for having the self-honesty and the honesty of others to see what was happening and make a decision - ironically, the qualities required of a Prime Minister."

Seymour acknowledged how Muller faced a tough week, with ex-National Party president Michelle Boag confessing to leaking confidential COVID-19 patient data to two National MPs, Hamish Walker and Michael Woodhouse. 

Boag has resigned her National Party membership and Walker - after admitting to leaking the information to the press - cancelled his plan to seek re-election in Southland. 

"Clearly, there's been some extraordinary issues around the National Party but every leader faces issues like that. Certainly, the test of leaders is whether they can get through these kinds of things," Seymour said. 

He also reflected on former National leader Simon Bridges, who in 2018 was accused of electoral fraud by one of his own MPs Jami-Lee Ross. Bridges denied the accusations and did not face charges. 

"Simon Bridges had a caucus member who was clandestinely recording him and trying to get him reported to the Serious Fraud Office."

Seymour is still confident National can triumph at the election with the right leader. 

"The next leader will have to deal with the three big issues of New Zealand today: how do we get smart about public health so we can safely reconnect with the world, how do we deal with our public debt problem, and how do we seize the opportunity of being an island nation on a pandemic planet for the next few years?

"Every election we find things can change even faster and this election I think could still very easily swing right because once you take away the politics, people still don't have answers to those underlying issues."

Green co-leader James Shaw

Green Party co-leader James Shaw wished Muller and his family well. 

"There's no denying that working in politics can take a personal toll and we wish Mr Muller and his family the best. We know that New Zealanders want policies and ideas, not politics," he said. 

"The Green Party is focused on delivering bold new ideas for Aotearoa, like our Poverty Action and Clean Energy Plans, and we're really excited to keep sharing our vision for a fairer Aotearoa as we move to the election."