The National Party has put its campaign on hold and has offered the Prime Minister its full support in the fight against coronavirus.
National Leader Simon Bridges said this afternoon that he has asked all National MPs to suspend all forms of campaigning.
"We want to do all we can to protect the lives and livelihoods of New Zealanders."
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He said he has offered the Prime Minister his full support during this crisis.
That is, provided the Government "moves expeditiously enough", Bridges said.
"We will work in a supportive and constructive way in the interests of New Zealanders."
He backed a move to Level four on the Covid-19 alert system – "I have expressed this to Jacinda Ardern".
The country is at level three and will move to level four on Wednesday.
Earlier this afternoon, Director-General of Health Ashley Bloomfield said two of the Covid-19 cases are believed to be community transmission.
Community transmission would almost certainly mean the alert level system would be moved up.
Bridges said the Government won't regret moving quickly to stop this virus spreading.
"We may have regrets if we don't," he warned.
"We will support the Government where we can. But we won't always agree and we will continue to let the Government know when we don't."
He said National MPs and candidates will still be in their communities offering help and advice to their constituents, giving out important information and advocating for them.
But they would not be doing any campaigning for the election for the "foreseeable future".
But this year's election will be on September 19, meaning the campaigning will begin in earnest around mid-July – which is also the middle of winter and flu season.
Ardern has said there are no plans to change the election date.
Justice Minister Andrew Little said he had asked Justice officials to ask the Electoral Commission to brief political parties on preparations for the election, and the possibility Covid-19 was still an issue in September.
He said the Electoral Commission had the power to adjust election arrangements – including other ways of voting - in case of an emergency, and he would leave it to them to make those decisions.