Foreign Minister Winston Peters said he had not been consulted on the moves by the Cook Islands, a small, self-governing Pacific nation that has a "free association" with New Zealand.

Wellington provides budgetary support and help on foreign affairs and defence to the former dependent territory, whose 17,000 people have New Zealand citizenship.

"Out of left field this has happened," Peters said in an interview with radio station Newstalk ZB.

"First of all, a demand to have a separate passport, so to speak, which would be dramatic in terms of our constitutional arrangements, and also the coming visit to China," he said.

Cook Islands Prime Minister Mark Brown says he will lead a delegation on a five-day state visit to China from Monday, and seal a Joint Action Plan for Comprehensive Strategic Partnership with Beijing.

He defended the visit Thursday, saying it was aimed at expanding economic opportunities "while ensuring our sovereignty and national interests remain at the forefront".

The China trip "has blindsided both the Cook Islands people and ourselves", Peters said, adding that Wellington had been asking for information for months but "it has not been shared with us or the Cook Islands people".

The visit comes at a sensitive time as China vies for diplomatic, economic and military influence in the strategically important Pacific region, challenging the historic sway of the United States, New Zealand and Australia.

The Cook Islands prime minister said in an interview published Friday that he had now ditched his passport plan because New Zealand "bared its teeth" by warning that anyone obtaining an island passport would lose their New Zealand passport.

Brown told the Cook Island News it was never his intention that a Cook Islands passport would be a travel document, instead describing it as a way of identifying people as Cook Islanders.

"We don't want to jeopardise our people and the safety and security of Cook Islanders. We will now put this onto the back burner," he said.

"I would say that it's off the table at the moment for us."