The Prime Minister will leave this weekend to travel to Europe and Australia for trade, tourism and foreign policy events.

Jacinda Ardern will also attend a session of the Nato summit in Madrid with leaders from Australia, Japan and South Korea.

Ardern said New Zealand was invited to attend the Nato summit as a partner of the treaty organisation.

"We will be discussing key security issues for the Indo-Pacific," Ardern said.

New Zealand is not a member of Nato, a Northern Hemisphere security alliance, but it has been invited in its capacity as one of the alliance's four Asia-Pacific partners, along with Australia, Japan and South Korea.

Ardern said she hoped to multiple European Union leaders, and would also meet with British PM Boris Johnson.

The PM said she hoped to discuss free trade with Johnson.

Ardern said her attendance at the Nato summit did not mean New Zealand was becoming more closely involved with the North Atlantic alliance.

"We have been, for roughly the past 10 years, a Nato partner."

The PM said New Zealand through a Nato trust fund had helped provide aid to Ukraine.

Ardern said she would continue promoting New Zealand's non-nuclear stance to Nato leaders.

She said current global instability made it imperative countries did not feel tempted to join the nuclear weapons club in misguided quests for security.

"Nuclear weapons represent a less safe world for all of us."

On additional assistance for Ukraine, Ardern said there were no announcements "here and now" to make.

Regardless of the geographic difference, New Zealand had "done our bit", she said.

It would be a protracted conflict and New Zealand was focused on seeking diplomatic solutions, and lending support in those areas too, she said.

If asked by Nato leaders for more assistance, Ardern said New Zealand was looking at the evolution of the conflict, not just looking through Nato but supporting countries surrounding Ukraine too.

"We've never said this is the end of our commitment," Ardern said when asked if New Zealand would be open to providing more assistance to Ukraine.

On former Defence Minister Ron Mark saying he will return to Ukraine, the PM said she didn't personally feel such a visit was especially wise.

"It's a war zone," she said.

Visit to Australia

After visiting Europe, the PM will visit Australia with a business delegation in Melbourne and Sydney.

She said the removal of pre-departure testing from midnight tonight would boost efforts to rekindle New Zealand's links with Australia.

On trade, Ardern said it was important for New Zealand to diversify its economy and deepen ties with the EU and the United States.

Legislation for a free trade deal with the UK will be introduced to Parliament ahead of Matariki, Ardern announced. The PM said New Zealand was also working on the closing stages of negotiations for a free trade deal with the European Union.

Earlier this month, Ardern announced she would return to Australia in July for talks between high-ranking ministers in both governments. Australian Prime Minister Anthony Albanese will also attend.

Ardern has a packed travel schedule this year, as part of New Zealand's post-Covid reconnection strategy, and she has previously said she would be travelling to Europe this year.

Also on the agenda in Europe is a long-awaited Free Trade Agreement with the European Union.

Farmers Weekly reported today that sector groups were concerned the Government would not push hard enough to ensure good market access in any FTA.

Sector leaders have flown to Brussels this week in what Farmers Weekly called a "last-ditch attempt to salvage worthwhile market access gains from trade talks with the European Union".

After a recess last week, Parliament returns to its regular sitting schedule this week.

Many ministers will have a busy week, with many scheduled to appear before select committees to answer for their budget bids in annual estimates hearings.

Ardern is also likely to speak to concerns over road safety in New Zealand following this weekend's tragic crash near Picton, which claimed seven lives.

It will be Ardern's first post-Cabinet press conference since the Tauranga byelection, which Labour's Jan Tinetti lost to National's Sam Uffindell.

Tinetti had been expected to lose the staunchly blue seat, but Ardern had been facing questions about the scale of Tinetti's defeat.

Tinetti lost by more than 6000 votes, with Uffindell posting nearly 10,931 votes to Tinetti's 4893.

"I think actually for byelections, it's very hard to read into them as someone who's run in a byelection myself because it's just simply not the same as in general elections, you don't often have every party represented, so I'm not quick to read into individual outcomes," Ardern told RNZ this morning.