National's Christopher Luxon has pulled out of The Press Leaders' debate, National has told Newshub.
It comes after Labour leader Chris Hipkins tested positive for COVID-19 on Sunday. He is currently in isolation.
A National spokesperson has told Newshub the party was prepared to do the debate on Tuesday night when it was originally scheduled and can't re-arrange Luxon's schedule to do it another time.
National is also not prepared to have Luxon debate a stand-in from Labour as it's meant to be a "leader-to-leader" debate, the spokesperson said.
The Press Leaders' Debate was scheduled to take place on Tuesday night, but with Hipkins being unwell and in isolation, the decision was made to postpone the event. But no alternative date has yet been found.
Joanna Norris, the managing director of Stuff's masthead publishing arm, said in a statement: "We are working hard with both parties to secure a date for The Press debate next week, once the Labour leader is out of isolation."
"At this stage, Mr Luxon's team have been unable to provide any alternative dates," she said.
"Thousands of people were looking forward to seeing both leaders in person in the only South Island debate, which is also live-streamed on Stuff. It will be a huge disappointment to a great many people, if this cannot go ahead."
Labour on Monday afternoon claimed Luxon was trying to take advantage of Hipkins being out with COVID-19 by attempting to get out of the debate.
Campaign chair Megan Woods said National is trying to use Hipkins' sickness to get out of the debate.
"Christopher Luxon must front up to tell Cantabrians and New Zealanders why he’s trying to slip out of an agreed debate with Labour leader Chris Hipkins in Christchurch," she said.
"Christopher Luxon is taking advantage of Chris Hipkins’ sickness by trying to slip out of The Press debate entirely.
"Despite Labour working constructively with the organisers and offering flexible dates next week when he is out of isolation, or an alternative to sub in on the original date if other dates don’t work - National looks like they are still declining Luxon to take part."
Woods said that National was "publicly proposing Nicola Willis or Chris Bishop should take his place, an admission after last week’s Newshub debate that Christopher Luxon just can’t cut it next to Chris Hipkins".
Senior Labour MP Grant Robertson said on Monday: "Christopher Luxon is running scared from Chris Hipkins."
"It is quite clear Christopher Luxon knows that he lost the last debate to Chris Hipkins, he has got a fiscal plan that doesn't add up, he has got a tax plan that doesn't add up."
Robertson said Luxon should find a date next week, like Labour has offered.
"Christopher Luxon has got something to hide from the New Zealand public and that is that his plans don't add up."
National's campaign chair Chris Bishop said it was actually Hipkins who had pulled out of the debate due to his illness and accused Labour of "desperate and dirty tactics".
"For the Labour Party to claim National is therefore pulling out of a debate that they themselves have said they cannot attend is absolutely ridiculous," he said.
He denied Luxon was chickening out.
"That is utterly infantile and stupid. The only person who has pulled out of a leaders' debate is the leader of the Labour Party and our Prime Minister, Chris Hipkins. That is facile and infantile, much like the Labour Party."
Luxon last week after the Newshub Leaders Debate admitted his performance was worse than in a clash the pair had the week prior. He also acknowledged making a "clanger" when he got mixed up about the legality of MDMA.
A Labour spokesperson on Monday morning said Hipkins was "still feeling quite unwell".
"He’s undertaking limited duties today, but aiming to pick up more things remotely from tomorrow, such as his morning media round."
Speaking at a policy announcement, Labour's commerce and consumer affairs spokesperson Dr Duncan Webb said Hipkins was "pretty rough".
"We probably won't be hearing from him today. But we are hopeful he will feel a bit better tomorrow and be able to hear from him then."