His statement, which followed talks with his father, King Norodom Sihanouk, lifts the threat of an immediate constitutional crisis.

All is calm in Phnom Penh now

However, he ruled out joining the government of his rival, Hun Sen, whose Cambodian People's Party (CPP) won the largest number of seats in parliament.

There has been more than a week of violence in the capital, Phnom Penh, after a government crackdown on opposition demonstrators contesting the outcome of the general election.

Caroline Gluck: "signs of torture"

The United Nations human rights monitor in Cambodia, Thomas Hammarberg, has expressed grave concern at the discovery of growing numbers of bodies around the city, some of them wearing the clothes of Buddhist monks.

The ruling CPP denies opposition allegations of fraud and irregularities. Most international observers described the election as generally free and fair.

But Prince Ranariddh said after his talks with the King in the northern city of Siem Reap that he could not join a coalition until his electoral complaints were dealt with.

Hun Sen does not have enough parliamentary seats to govern alone.

Hopes for summit

A summit between the leaders of the three main parties, to be hosted by King Sihanouk, is being organised to defuse the political crisis.

The BBC correspondent in Cambodia, Caroline Gluck, says the meeting might address the opposition's demands. If not, it could take some time before a new government is formed, and more uncertainty for the country.

Clashes went on for eight days

At least two people have died and many others have been seriously injured in the government's crackdown on opposition protests.

The UN says more than 16 people have been found dead since then in rivers, ditches and shallow graves around Phnom Penh, and increasing numbers of people have been arrested or have disappeared.

An Interior Ministry spokesman, Khieu Sopheak, said there was no evidence to connect the incidents with the government's action to halt opposition demonstrations.

On Monday, the ruling party and its two main opposition rivals agreed to the cessation of demonstrations, a summit meeting of party leaders hosted by King Sihanouk, and the convening of the National Assembly as planned on 24 September.