His younger brother, Crown Prince Tupouto’a Lavaka, who is heir to the throne, was with him when he died, aged 63, while on a visit to Hong Kong, Television New Zealand said. Tongan radio read a government statement announcing his death.
On ascending the throne, the Oxford-educated king said he would relinquish most of his power in the last Polynesian monarchy and be guided by his prime minister’s recommendations on most matters.
The first direct elections were held in November 2010 after 165 years of feudal rule.
Tonga, which comprises 170 islands, has a population of about 100,000 and lies south of Samoa, about 2,120 km (1,320 miles) northeast of New Zealand.
The king was known to the outside world for eccentricities such as being driven around in a London taxi.
