WELLINGTON (REUTERS) - New Zealand Prime Minister Jacinda Ardern said on Monday (March 23) the country will move into its highest alert level, with all non-essential services, schools and offices to be shut over the next 48 hours.

The move means bars, cafes, restaurants and cinemas will be shut. Supermarkets and pharmacies will remain open, Ms Ardern said, adding that the country was well supplied.

All schools will be closed from Tuesday, she said.

"New Zealand is now preparing to go into self isolation," she told a news conference.

The measures, which will remain in place for at least four weeks, are aimed at breaking the chain of community transmission, she said.

Without them, her advice is that tens of thousands of lives will be at risk and health services would be inundated.

“These decisions will place the most significant restriction on New Zealanders’ movements in modern history,” Ms Ardern said. “This is not a decision taken lightly. But this is our best chance to slow the virus and to save lives.”

The number of coronavirus cases in New Zealand rose above 100 on Monday as the country reported 36 new infections amid growing pressure on the government to further tighten restrictions to contain the outbreak.

The nation’s top-50 share index plunged 10 per cent on Monday, extending its decline since Feb 21 to more than 30 per cent.

Appearing with Ms Ardern, Finance Minister Grant Robertson unveiled a range of new economic stimulus measures. He said the government will expand its wage subsidy scheme to all affected businesses, lifting the cost to NZ$9.3 billion (S$7.65 billion) from NZ$5.1 billion, to ensure all workers receive some form of income during the lockdown.

Other measures include a freeze on rent increases and leveraging the Crown balance sheet to allow banks to extend lending to firms.

Earlier, New Zealand's opposition National Party said it had put on hold its campaign for a general election on Sept 19.

"This morning I have asked all of our MPs to suspend any form of campaigning," said Mr Simon Bridges, leader of the main centre-right opposition National Party.

Mr Bridges called for the government to raise alert levels in the country to its highest, level 4. "We won't regret moving quickly to stop this virus spreading. We may have regrets if we don't," he said.