The president of the Cook Islands Democratic Party, Sean Willis, says the death of Sir Terepai Maoate is a huge loss to the country.
The former Prime Minister died aged 77 after a long battle with prostate cancer.
The government is planning a state funeral and Sir Terepai's family says it will be held on Friday Cook Islands time.
Mr Willis says Sir Terepai's work ethics as a medical doctor also translated into his political life.
"He was doing long hours each day, doing about 90 hour week just attending functions plus carrying out his normal work and also doing his favourite past time as all the people know was planting. So he still carried on as a planter, fisherman and everything else whilst putting in the long hours as a politician. It is a big void, not only for the family but for the people of the Cook Islands."
The president of the Cook Islands Democratic Party, Sean Willis.
