Seasonal workers from Tonga, Samoa and Vanuatu will be allowed into the country without having to go into managed isolation from September, the government says.
In a post-Cabinet media briefing this afternoon, Ardern announced Cabinet had made the decision to allow Recognised Seasonal Employer (RSE) workers from those countries to travel one way, without using MIQ.
The countries this would apply to reflected the fact all three nations had experienced very few cases of Covid-19, she said. Tonga had seen zero Covid-91 cases, Samoa just one, and Vanuatu had four - all those cases having been at the border with no community transmission.
"We know our agricultural sector is experiencing challenges," she said. "We've heard the call from Primary sectors and others to bring in additional workers in a safe way and we think that is now possible.
"We'll be working through some of the detail including repatriation ... so that we don't risk stranded workers."
The government is also looking at additional health precautions for the workers.
She said 150 workers were being brought in every 16 days but this would open up for significantly more.
The government did not know the exact number of additional RSE workers expected to come in, but Ardern there were about 7000 in New Zealand right now and the norm was about 10,000. One of the constraints is the one-way nature of the restriction-free travel, she added.
"Travellers would still undergo quarantine on return to their home country, as has been their home country's policy."
Immigration Minister Kris Faafoi told the media gathering he had been speaking to the industry, and businesses were keen to work with the government on ensuring there are enough workers to meet the demands of the horticulture sector.
The government in May announced an expansion of Recognised Seasonal Employer (RSE) and other seasonal workers into New Zealand, and in June announced an automatic six-month extension to Working Holiday and Supplementary Seasonal Employment visas, and expanded its categories to all industries.
However, industries have remained concerned at what they said was a continued lack of staff, with the hospitality industry in particular frustrated over visa settings, exacerbated by the resumption of restrictionsfor travel from Australia.
Unions have claimed the hospitality shortage is due to low wages or lack of a viable careers in the industry rather than lack of labour.
In April, a report found the RSE scheme was not a benefit to the wider economy.
The prime minister said she would reveal further changes to the border over the next six months, starting with a forum to share advice to the government from the advisory group led by Sir David Skegg.
Ardern said Cabinet would be willing to consider allowing people in who may have critical medical conditions from one of the countries where quarantine-free RSE workers will be allowed to travel from, but wanted to get the system up-and-running first.
Covid-19 Response Minister Chris Hipkins said such people would need to be in a dire medical situation to allow for that.
Hipkins says he was also checking on whether the settings were right for people in New Zealand now who need to travel overseas for treatment.
He also said the government did have systems in place to review individual cases and urged people to make use of those.
Ardern said there was however a lot of demand right now for MIQ. "There are peak points where, for instance, in April and May we had capacity. The minister at that time urged New Zealanders to come home..."
She said the minister was looking at settings changes to make the system fairer, including the voucher system.
Hipkins said the increase in demand for MIQ had changed quickly, going from thousands of vouchers available to next to none within the space of a few days. He said the government was considering issues of fairness to make sure everyone was getting a fair opportunity to get back to New Zealand.
There had been opportunity for New Zealanders to come back, but the reality in a global pandemic was travel was going to be difficult and expensive and "people should grab whatever opportunities they can get", he added.
He said it was challenging to match timings of room availability with flight availability, calling it a "huge logistical undertaking".
Cabinet is also seeking advice on whether to allow people waiting for residence visas to stay in New Zealand longer.
Ardern said she wanted New Zealanders to come home if they desired to, but she wanted them to come back to a safe New Zealand and the border management had been part of what has kept the country safe.
Ardern said she would from today provide an update on vaccinations each week.
She said more than a quarter of a million New Zealanders had been vaccinated last week, after the success of the mass vaccination event in Auckland, and rejected claims there was a syringe shortage.
"We will likely see more mass vaccination events like this over the coming months," she said.
Last week some 76 sites were brought on to provide vaccinations, including on Rakiura/Stewart Island, which was open to all the residents there, Ardern said.
The Prime Minister also commented on the Human Rights Commission's inquiry into housing. The Commission stated successive governments had failed to live up to the promise of creating the conditions to enable everyone to live in a decent home.
Ardern said the commission was an independent body and had the prerogative to look into whatever they considered necessary, but that it had acknowledged the work the government had carried out to provide for address the country's housing need.