By Sarah Robson
Thousands of Cook Islanders are expected to turn out to celebrate 50 years of self-government in free association with New Zealand.
Prime Minister John Key, along with a large delegation of Government ministers and other MPs, is in Rarotonga to mark the constitutional milestone.
Tuesday (local time) is Constitution Day and there'll be a number of official events to celebrate the Cook Islands' world-first constitutional arrangement with New Zealand.
"Thousands of Cook Islanders are expected to turn out to celebrate the occasion and it is a great privilege to be here to mark it with them," Mr Key said.
Mr Key held talks with Cook Islands Prime Minister Henry Puna after he touched down in Rarotonga on Monday.
The pair canvassed a range of issues, including New Zealand's $42 million aid contribution over the next three years.
Self-government in free association isn't the same as full independence.
Cook Islanders are New Zealand citizens, have New Zealand passports and use New Zealand currency.
But the Cook Islands government is free to make its own laws and conduct its own affairs.