Finance Minister Grant Robertson told RNZ on Monday the deal should be seen in "context".
"We've had the UK deal, others are negotiating with the EU at the same time. So, we're committed to this, we're at the table, but we're going to get a good deal for New Zealand.
"I'm confident that New Zealand exporters are going to benefit significantly from the deal that we're working on. I'm confident this will be a good deal," he said.
Ardern's meeting with Sánchez will also give her the opportunity for his help with New Zealand's vaccine rollout. Last year, Spain supplied much-needed doses of vaccine when New Zealand hit a supply snag.
The meeting with Macron will discuss trade and Nato.
Ardern's meetings will take place at the sidelines of the Nato leaders' summit, which Ardern is attending as a guest. New Zealand is not a member of Nato, a strategic defence alliance of European and North American countries.
The trip is not all trade and war: Ardern will cap off the day at a ritzy dinner hosted by Spanish King Felipe VI at the Palacio Real [Royal Palace].
She will also give a speech at a technology and democracy event, which will likely look at themes she explored in her Harvard commencement speech this year, like the way new technology can polarise society.
One of the reasons Ardern is keen to attend the Nato summit was not for defence at all, but because it will give her the opportunity to speed-date the host of EU leaders in attendance, making the case for a better trade deal.
Along with Sánchez and Macron, she has bilateral meetings with Dutch Prime Minister Mark Rutte (the Netherlands is said to be a particular holdout on trade talks), and German Chancellor Olaf Scholz.
Speaking to the Herald ahead of her trip, Ardern appeared to manage expectations of a trade breakthrough for agricultural products. Primary sector leaders recently flew to Brussels after reports that any deal might not deliver significantly better terms for them.
Ardern acknowledged that "dairy and beef is very sensitive for the EU".
"Right now, we're negotiating with 25 plus economies and negotiating teams. It's very complex".
While she appeared to manage expectations around beef and diary, she appeared optimistic on other goods.
Ardern's presence at the summit is in part recognition of New Zealand's participation in the response to Russia's invasion of Ukraine. Much of New Zealand's aid to Ukraine has been sent via Nato.
Ukraine is expected to feature heavily on the agenda with questions being asked about the alliance's long-term strategy to bring an end to the war and a halt to Russian aggression. Ukrainian President Volodymyr Zelenskyy is scheduled to address the summit via video link.
But Ardern is not the only non-Nato leader in attendance. The leaders of South Korea, Japan, and Australia have also been invited as Nato looks to discuss threats to its security from beyond the Atlantic region, namely China.
Macron was a late addition to the trip, which did not originally include a one-on-one meeting with him. Ardern's first event is scheduled for late this evening, New Zealand time.
