Foreign Minister Murray McCully has taken Shane Jones, David Shearer and Winston Peters with him for his trip to the Cook Islands, where he is holding talks on dwindling island populations and renewable energy.
The delegation's three-day visit, which kicked off yesterday, will reach some of the country's most far-flung atolls, 1300km north of the capital of Rarotonga.
Mr McCully's office said New Zealand First leader Winston Peters and Labour's foreign affairs spokesman, David Shearer, were on the trip because the minister wanted cross-party support for New Zealand's work in the Pacific.
Mr Peters also had a strong interest in the Cook Islands when he was Foreign Minister.
Former Labour MP Shane Jones joined the group as Ambassador for Pacific Economic Development, and would be expected to oversee any decisions which came out of the tour.
The Opposition MPs will not take part in Mr McCully's talks with Cook Islands Prime Minister Henry Puna or Opposition leader William Heather.
The trip started at Penrhyn Island, the most remote atoll, known for its picturesque lagoon and pearl diving.
With just two villages and a shrinking population, Penrhyn's community was having sensitive discussions with Mr McCully about whether the Penrhyn community was still viable. The number of residents dropped from 351 in 2001 to 213 in 2011, and was believed to have fallen further to around 150 people.
The minister and Mr Puna also opened solar-powered projects on Penrhyn and Manihiki islands.
The Government has allocated $20.5 million for solar projects in the Cook Islands as part of its commitment in 2013 to invest $65 million on energy supply in the Pacific. The more sustainable and secure energy sources had already allowed residents on other atolls to save on diesel bills and invest in electric appliances such as refrigerators and freezers.
The delegation will today inspect a cyclone shelter on Manihiki Island. The New Zealand Aid Programme donated $1 million for two shelters on the island, which is just a few metres above sea level.
Mr McCully said in a statement that New Zealand and the Cook Islands had a "special relationship", and he planned to celebrate the 50th anniversary of the Cook Islands' self-government during the trip.
"We will meet with Prime Minister Henry Puna to discuss arrangements for the anniversary, regional issues, and our development assistance to the Cook Islands," he said.