WELLINGTON:New Zealand's prime ministerial hopefuls clashed on Thursday in their last debate before a general election that Prime Minister Jacinda Ardern said if she does not win, she will resign from the leadership of her Labour Party.

An opinion poll on Thursday showed Ardern, 40, had a comfortable two-digit lead over her main rival, National Party leader Judith Collins, and was on course to win Saturday's election on the back of her success in tackling the novel coronavirus in New Zealand.

In addition to her pandemic response, Ardern has won support at home and global admiration for her response to last year's attack by a white supremacist on two mosques and a fatal volcanic eruption.

The closely watched 1News-Colmar Brunton poll on Thursday showed support for Ardern's party slipped 1 percentage point to 46% from the previous poll on Oct. 8 but maintained a 15-point lead over the National Party, which slipped a point to 31%.

This means Labour would have 59 seats in parliament, just short of the 61 needed to form a government on its own.

Labour's likely coalition partner, the Green Party, bounced back to its highest level since 2017 with a support of 8%, which would give it 11 seats.

If the parties join hands that would produce the country's first pure left-leaning government since 1999.

Labour's other current coalition partner, the nationalist New Zealand First, led by Deputy Prime Minister Winston Peters, got an uptick to 3% but that still leaves it on course to exit parliament with no seats.

"I will make whatever New Zealand voters deliver, work," Ardern said in the debate when asked if she would work with Greens or NZ First.

"What I am very clear on is that we will get things done faster, with a strong mandate and that's what I'm asking for Labour."

Ardern said Collins' assertion that child poverty had become worse was "factually incorrect" and said she was spreading misinformation by saying Labour would introduce a wealth tax.

Ardern also declared if her party loses, she will not stick on as leader of opposition.

"My message would that be if people don't want to see me resign, then vote for Labour," she told media after the debate.

Despite her success in handling crises, questions have been asked of Labour's credentials to tackle the looming economic crisis.

Collins has focussed her campaign on the financial challenges ahead as unemployment rises, recession looms and the government's coronavirus support packages expire.

The 61-year-old conservative has warned a left-leaning coalition would mean more taxes and a business-unfriendly environment.

"We are moving into very difficult economic times. We need a party that understands business and makes decisive decisions about what happens in our economy. So our plan is all focused on the economy," Collins said.

Ardern's popularity as preferred prime minister has jumped to 55%, leaving Collins behind at 20%, the polls showed.