East Coast MP Anne Tolley is backing embattled National Party leader Simon Bridges.

Mr Bridges is facing a challenge from Bay of Plenty MP Todd Muller, which will be decided at an emergency meeting of National's caucus tomorrow.

Mrs Tolley described the bid to oust Bridges as potentially destructive, “stupid” and “nutty stuff”.

“It's a bit of panic from some of the newer MPs who have only been there since the halcyon days of John Key.

“They're quite used to seeing National in the mid-40s (in the polls). They have not experienced the ups and downs.

“They have no idea of what it's like when times get tough.”

Mrs Tolley first entered Parliament in 1999 when the three-term Helen Clark-led Labour coalition Government was elected.

Ms Clark rated at 3 percent in opinion polls and was considered unelectable only to become one of the country's most respected prime ministers said Mrs Tolley.

Those campaigning against Mr Bridges had held concerns for some time and decided to act after a Newshub/Reid Research popularity poll showed National on 30.6 percent and Labour at 56.5.

They did not have the numbers for a leadership challenge and it was likely there would be a vote of no confidence instead.

Mrs Tolley said they had not approached her for support. They were hoping to fracture the caucus and “come up the middle”.

A vote of no confidence was destructive. It could destroy a leader and leave a vacuum, she said.

“Why the hell would you do that? It never happens. Three months from an election — it's nutty stuff.”

Mr Bridges would meet his opponents “head-on” tomorrow at an emergency caucus meeting, she said.

Mrs Tolley conceded Mr Bridges had received criticism during the lockdown.

“I keep telling people that Leader of the Opposition is a tough gig. You have to ask the tough questions. That is the role of the Opposition.

“You can't be Mr Nice Guy all of the time.''

National believed lockdown restrictions had been too severe during alert levels 3 and 4 and that the country could have moved to Level 2 earlier.

The Government had bowed to public pressure and allowed larger attendances at funerals and tangi. But similar liberalising of attendance restrictions had not been applied to faith services.

It was a human rights matter, she said.

Mrs Tolley is standing as a list candidate only in September as she hopes to move up from Deputy Speaker of the House to Speaker.

The new National Party candidate for East Coast will be selected on June 6.

Mrs Tolley has held the seat for National since 2005.

With National at 30.6 percent and Mrs Tolley's last party list position at 21, she said: “I won't be there”.

“That is the risk I take.”

She was hopeful of a higher list ranking in 2020 if the party wanted her as Speaker.

“I do not believe we will be on 30 percent on election day.”

National had suffered from little media exposure during the lockdown, with the Prime Minister on television every day, she said.

She described Jacinda Ardern as “an amazing communicator in amazing circumstances”.

National was perceived as a strong economic manager and the economy would be the key issue during the election.

She intended to work hard now the lockdown had ended and was looking forward to meeting people in the electorate.