The Prime Minister says Kiribati's departure from the Pacific Islands Forum won't detract from the group's first meeting in several years.
Kiribati announced it was withdrawing just days before leaders are set to gather in Fiji.
It's thrown up fears for the region's unity in the face of China's growing influence and the ever-growing impact of climate change.
Before she's even left the Beehive for Suva, Prime Minister Jacinda Ardern was on Monday fielding questions on a fresh rift in the Pacific Islands Forum - Kiribati has announced its departure from the regional body.
"It is disappointing that Kiribati don't feel that their concerns have been met," Ardern said.
It's a brutal blow for the Forum on the eve of a critical face-to-face for leaders as the Pacific faces geopolitical manoeuvring from China and the US.
"Would it be preferable for everyone to be at the table? Absolutely. Will it stop us continuing work in those areas that even Kiribati identify as being critical for the region? No."
It was a bombshell from the Kiribati Prime Minister just days out from the leaders' meeting.
A letter to the Forum reads: "Kiribati has taken the sovereign decision to withdraw from the Pacific Islands Forum with immediate effect."
Among the reasons were the Forum's "collective inability… and reluctance to address the core concerns" raised by Kiribati - including the Secretary General's appointment.
"A misstep which does not allow the usual courtesies to discuss matters in the Pacific way," the letter said.
Ardern said "there is a view that issues like climate change which affect all of us, we must keep working collectively on and my hope is over time, Kiribati will choose to come back into the forum".
Kiribati's departure has stoked fears that China's push to expand its influence is fracturing the Pacific's solidarity. The Prime Minister doesn't want to weigh into the 'why'.
"I wouldn't want to second-guess their decision and attribute it to something entirely separate when they have set out their own reasons."
Regional unity is critical now more than ever to tackle the Pacific's key threat - climate change - and the Prime Minister is adamant Kiribati's departure won't derail efforts there.
"This is such a pressing issue for our region, being able to come forward and say this is number one for us, and here's our ask of the global community, that is incredibly powerful and important."
Pacific politics are heating up while the leaders are hopeful they can hold the Forum together.
