She said she wanted to hear Australia's view on the risk of a vaccinated person mingling in an unvaccinated group - which immunologists say could lead to an outbreak.
"We're keeping an open mind because we are continuing to see the data and evidence come out. We're not rushing to conclusions either way," Ardern said.
"Given our transtasman arrangement, there is real benefit in us talking about how we view that possibility, how our health officials view some of the data on the risk of vaccinated persons in terms of transmission, and our views on vaccine passports."
The last meeting they had was in February last year, the day of New Zealand's first Covid case.
Morrison, accompanied by his wife, will arrive in Queenstown on May 30 and talks will take place the following day.
Ardern and Morrison will engage with Australian and New Zealand business, tourism, and community leaders, and lay a wreath at the Arrowtown War Memorial.
They will also attend the Otago Highlanders-Melbourne Rebels game.
Ardern has previously used such meetings to press home her dissatisfaction with Australia's 501 deportation policy.
Ardern may also seek an update on Suhayra Aden, the former Australian-New Zealand dual citizen alleged by Turkish authorities to be an Islamic State terrorist. Australia revoked Aden's Australian citizenship, prompting a sharp rebuke from Ardern for abdicating its responsibilities to its citizens.
Both countries' relationships with China are also likely to be discussed.
This follows questions over whether New Zealand's stance on China is soft due to a reluctance to upset its biggest trading partner, and why New Zealand has been absent from some Five Eyes' statements critical of China limiting Hong Kong elections.
New Zealand has at times joined the Five Eyes' statements, and other times spoken out on the Hong Kong issue by itself.
Foreign Minister Nanaia Mahuta has said that she was "uncomfortable" using Five Eyes to comment on non-security matters.
Last month Australian Foreign Minister Marise Payne, in a visit to New Zealand, declined to criticise New Zealand for not endorsing more of Five Eyes' statements.
Payne also did not push for New Zealand to take a stronger line on China, saying she had learned "not to give advice to other countries".
She said Australia's stance on China has offered "clarity, consistency and confidence", which has contributed to the security and prosperity of the region.
Ardern is also leading a business delegation to Australia in July.
Budget unveiled on Thursday
On Thursday the Government will unveil its spending priorities for the coming year in Budget 2021.
Regarding the Budget, Ardern said it was about making sure New Zealand came out of Covid stronger than when coming into it.
The economy had performed better, unemployment better than expected, all due to "careful" management, she said, and that would continue.
The immigration announcement was about looking at what New Zealand's needs were, she said.
New Zealand had the highest reliance on temporary workers in the OECD.
"We need to move away from relying on overseas labour to support our economy."
The immigration reset was not about "crude numbers" but the outcomes New Zealand - and those coming here - were after, Ardern said.
For too long New Zealand's reliance on a low-paid workforce as not working for them or New Zealand, she said.
Asked about RSE workers specifically, Ardern said this would not be touched.
That was not just about labour shortages in New Zealand, but providing opportunities for people in Pacific islands countries.
Cook Islands bubble
Today's Cabinet meeting also comes on the first day of the quarantine-free travel bubble between New Zealand and the Cook Islands.
The first flight to Rarotonga will touch down tomorrow, and there will be daily flights between the two countries after that.
Ardern said the Cook Islands bubble was another step in the recovery process, offering the chance for families to reconnect, help businesses and give some a "well-earned break".
Regarding the Cook Islands bubble, if there was a Covid case it would likely have originated from New Zealand. That was why it had been a cautious reopening as it would be New Zealand's responsibility to assist with any potential outbreak there.
That could lead to New Zealand bringing people back here to relieve pressure, she said.
This would also apply to Cook Islanders themselves, as per New Zealand's current arrangements and "expectactions" to provide urgent care when required, she said.
Latest poll reaction, Israel and Palestine
On Sunday the latest poll from Newshub-Reid Research showed Ardern and her party Labour's popularity holding steady.
Meanwhile, National Party leader Judith Collins' preferred PM stakes has taken a dive, following weeks of the party accusing the Government of a "separatism by stealth" agenda.
Results from the poll showed Labour at 52.7 per cent (up 2.7 percentage points from election night), and National at 27 per cent (up 1.4 percentage points).
In the preferred PM stakes, Jacinda Ardern polled 48.1 per cent (down 4.5 percentage points); Judith Collins was at 5.6 per cent (down 12.8 percentage points).
Ardern has also been pressed on New Zealand's position on the escalating conflict between Israel and the Palestinians.
In just seven days at least 188 Palestinians have been killed in Gaza, including dozens of women and children, and 10 people killed on Israeli soil.
Asked about New Zealand sending military equipment to Israel, Ardern said they were advised none of this was used in the current conflict.
These products were samples, she said.
Approval would not be given for these to be used or sold for military purposes, she said.
With the existing export regime they could not prohibit exporting samples but they could prohibit them being used for military purposes.
It seemed like a "pointless" exercise for those involved, she said.
New Zealand continues to support a two-state solution, one for Israelis and one for Palestinians, with Jerusalem as the capital for both states, but the latest fighting was pushing that outcome "further and further away", Ardern told 1News today.
"So long as you have the threat of evictions of Palestinian families, and so long as we have in response from Hamas indiscriminate rocket fire, and then so long as you have Israel responding to that with a response that goes beyond self-defence when you start seeing the death of women and children, then we move further and further away from that two-state solution."
On Samoa potentially having their first female prime minister, Ardern said it seemed "significant".
