Wellington - The Pacific island state of Tonga, which remains under martial law following pro-democracy riots that destroyed most of the capital Nukualofa 18 months ago, is planning a lavish coronation for its new King George Tupou V, a newspaper reported on Thursday. British pop stars Sir Elton John and Mick Jagger are on the guest list for a five-day celebration honouring the 60-year-old king who succeeded his father in September 2006, the Dominion Post in Wellington reported, citing leaked information from Tonga.

The Tonga Review website, which reports government statements, said that emergency rule declared after the November 2006 riots would remain in force during the coronation from July 30 to August 3 because of threats of political demonstrations by the democratic movement.

"This may cause some anxiety amongst foreign dignitaries so this could prevent some from attending," the website said. "It is rumoured that most of the European and Asian royal families have been given invitations along with other world leaders."

Pro-democracy campaigners made a clean sweep in Tongan elections last month but remain outnumbered in parliament by legislators appointed by the king and the traditional chiefs, or nobles, who support him.

The Tonga Review said the coronation would cost about 4 million New Zealand dollars (about 3.2 million US dollars) but quoted government sources as saying organisers were running out of money and the bill could double.

Foreign analysts estimate that nearly one-quarter of Tonga's 119,000 people live below the poverty line and the economy depends on international aid and money sent home by citizens who have emigrated to New Zealand, Australia and the United States.

The November 2006 riots broke out five weeks after the succession of the bachelor king, who had been widely seen as a playboy crown prince.

Although the royal family, chiefs and representatives of the common people have been negotiating a change to a more democratic political system, pro-democracy campaigners say progress is slow and they are running out of patience.