Prime Minister Jacinda Ardern will meet her Japanese counterpart Fumio Kishida for the first time this evening.
Ardern and her trade delegation arrived in Tokyo overnight, the second leg of their trip to Asia after two days in Singapore.
Japan is still operating under strict pandemic restrictions - with their border still closed to tourists - and mask use is required inside and outside.
The rules may curtail some of Ardern's interactions, but she begins with a promotional event for Zespri to mark the start of kiwifruit season.
She will later sit down with Japan's prime minister Fumio Kishida, their first encounter after his election last year.
China's growing influence in the Indo-Pacific is sure to feature in their conversations, after the country announced the signing of a security deal with the Solomon Islands.
A draft of the deal's text was leaked last month, showing it would allow China to deploy military and police forces there, and make ship visits.
The final version has not yet been released however, and both China and the Solomons have denied it would open the door to a Chinese military presence in Honiara.
China's Foreign Ministry spokesman Wang Wenbin said it would involve cooperation on maintaining social order, protecting people's safety, aid, combating natural disasters and helping safeguard national security.
Solomon Islands prime minister Manasseh Sogavare said its aim is for the nation to diversify its security ties and address "soft and hard" security threats facing the country.
New Zealand has called the pact gravely concerning and Japan has also expressed alarm.
Ardern yesterday said New Zealand saw no need for the deal, and expressed frustration the Solomon Islands had not talked to the Pacific Islands Forum before signing.
"Simply put there is no need for this agreement that they have signed and we ask and continue to ask for dialogue with the whole region, not just New Zealand."
She also referred to the Pacific Islands Forum's Biketawa Declaration, an agreement in 2000 which allows members to respond to breaches of governance, democratic freedoms and indigenous rights with a combined response up to and including fact-finding missions, mediation, or sanctions.
When questioned on a need for New Zealand to diversify away from its economic reliance on China, she said it was important for New Zealand exporters to build resilience.
"What it means is looking at where there may be potential vulnerabilities, disruption, planning for that ... that's for many reasons. Covid demonstrated that at any given time your market can reduce down very very quickly."
National's Foreign Affairs Spokesperson Gerry Brownlee said it showed the relationship between the Solomons, New Zealand and Australia was nowhere near the level New Zealand had thought.
"I think that's a very big diplomatic failing ... there does have to be a question asked about why has that relationship broken down to a point where a commonwealth country can look well outside its natural friends for a security arrangement," he said.
"If we can't compete with the chequebook then I think, you know, you really do need to think about the strength of the relationship and that's where I think we've been a little bit let down by our diplomatic services."
He said New Zealand should consider extending its existing peacekeeping deployment in Solomon Islands, given growing volatililty in the region.
All members of the travelling delegation took saliva PCR tests on arrival in Tokyo, all returning negative results.
The trade delegation is however short by three members who returned weak positive Covid-19 test results from previous infections while in Singapore, and were unable to go to Japan because of the strict rules.
The delegation will spend two more nights in Japan before returning to New Zealand.