Australian cruise brand P&O Cruises is closing, and a ship that regularly sails in and out of Auckland will be removed from the fleet.
P&O's parent company Carnival Corporation will fold the operations into its flagship Carnival Cruise Line brand early next year, it said.
The Pacific Explorer will be retired after next February, while the Pacific Encounter and Pacific Adventure ships will be rebranded.
Anyone booked on the Pacific Explorer from March next year will be refunded, P&O Cruises said.
"All itineraries on Pacific Explorer scheduled to sail after 2nd March 2025 are being cancelled," it said.
"If you are booked on one of these itineraries you will be contacted by Guest Services in the coming days with refund details."
The South Pacific's small population, and significantly higher operating and regulatory costs led to the decision to close the brand, Carnival Corporation's chief executive Josh Weinstein said.
Carnival Corporation would remain committed to Australia where it was the largest cruise operator in the region with 19 ships calling on 78 destinations, he said.
The company has 60 percent of the market share.
"P&O Cruises Australia is a storied brand with an amazing team, and we are extremely proud of everything we have accomplished together in Australia and the broader region," Weinstein said.