National leader Bill English emerged from the first day of his party's caucus retreat saying support for him was not an issue and he was "not surprised" MPs were backing him in the job.

The caucus retreat in Tauranga was preceded by a bout of leadership speculation with unnamed MPs saying they were preparing for the possibility English would stand down and suggestions there could be an attempt to roll deputy Paula Bennett.

At the retreat, MPs including those considered likely to stand for the leadership if English did stand down, were publicly backing him and Bennett to stay on until 2020.

"I'm not surprised, " English said. "I've had strong support from the caucus and the party and from the large number of voters who voted for us, so support for me is not an issue."


English has said the prospect of resigning after National was sent to Opposition had crossed his mind immediately after, but he was re-elected National leader in late October by the caucus.

He is not ruling out going before 2020, saying it will depend on his performance and whether he retains public and caucus support.

English said the MPs were naturally disappointed about being in Opposition but were getting to grips with the work it entailed and putting National forward as an alternative government.

"It is not a dispirited and scattered Opposition. They are in pretty good shape."

He said the caucus had done an "honest appraisal" of the election campaign but would not say what the mistakes were.

"There's any number of things that could have been done differently that would have got us into Government."

Asked if his own call to "cut out the middle man" in reference to NZ First leader Winston Peters was one of them, he said he did not want to go into the details.

The party was now focused on 2020.

There were also questions about which MPs might leave early after the inclusion in the caucus meeting of the "reserves bench" - the four candidates next in line to enter Parliament off the list.

They are former MP Maureen Pugh, Nicola Willis, Agnes Loheni and Paulo Garcia.

Those considered most likely to leave include David Carter, who would not rule it out, saying only "I'll make a decision when I'm ready to make a decision."

Chris Finlayson said he had no plans to leave while Nelson MP Nick Smith said he would remain for the whole term and make a decision on 2020 in about 18 months' time.

Ilam MP Gerry Brownlee, asked about his future, said only "it's looking bright" and walked away.

Those publicly backing English included Simon Bridges who is considered almost certain to try for the leadership if English quits.

Bridges said he believed the party could go into 2020 under the same leadership team but would need to make changes.

"Any government, and we were in government for nine years, doesn't get everything right. And we'll need to evolve with the times.

But I think we can definitely do that with our current leadership."

Bridges would not discuss his own ambitions, saying he did not deal in hypotheticals and did not believe English would quit.

Asked he believed he could do a better job than English he replied "no".

Dr Jonathan Coleman, who initially put his hand up for the leadership against English when former Prime Minister John Key resigned, also said he believed English was the right person to take them to 2020.

"Bill's had a great mandate from the public, he's doing very well as the leader and people are right behind him."

One of the potential future leadership candidates, Nikki Kaye, will leave early to go in the Coast to Coast Race tomorrow for the first time in five years after her battle with breast cancer.

MPs were in good spirits at the conference and many brought their spouses for the social events. Mary English was among those there.