Party spokesman Khieu Kanharith said the CPP was on course to win 91 of the 123 seats in Parliament.

However, the claim was disputed by Cambodian opposition leader Sam Rainsy.

'Neither party won more than two-thirds of the seats,' he told reporters, estimating that no party garnered more than 70 seats each, according to a tally by his supporters.

A member of his Sam Rainsy Party (SRP) said that early results suggested it was on course for at least 40 seats, although Mr Sam Rainsy, a former finance minister, put his projected tally much higher.

The SRP also cried foul over elections in districts around the capital, saying voters were wrongly struck from the rolls.

The party, which held 24 seats in the last Parliament, claimed that 200,000 of Phnom Penh's 722,000 voters had not been able to cast ballots because of irregularities with the electoral lists.

'We don't accept the result in Phnom Penh,' Mr Sam Rainsy said. 'I demand a re-run of the election in Phnom Penh to bring justice to voters.'

He added: 'I call for a demonstration in Phnom Penh. I appeal to all people whose names were unfairly deleted - please hold a huge protest in Phnom Penh.'

Election observers said they had confirmed cases of voters having their names removed from the rolls, but said they had doubts the problem was as widespread as Mr Sam Rainsy claimed.

'The atmosphere for election day was better than in past elections. But the most prominent point is that the turnout was low and a lot of names disappeared' from the rolls, said Mr Hang Puthea, who heads the Neutral and Impartial Committee for Free and Fair Elections in Cambodia, a local election monitoring group.

'I can't believe that as many as 200,000 names went missing. I could believe it if the number was maybe 20,000,' he added.

CPP spokesman Khieu Kanharith told reporters: 'We don't need to commit fraud to win.'

Mr Hun Sen has been widely tipped to win the election because of booming economic growth and soaring nationalist sentiment sparked by a border stand-off with Thailand. The two countries are locked in a dispute over land around the Preah Vihear temple.

More than eight million of Cambodia's 14 million people were eligible to vote in yesterday's election.

Eleven parties vied for seats in the National Assembly, the lower house of Parliament.

Full results from the poll - which was completed largely without incident in a country where democratic politics have frequently been marred by violence - are not expected until late today.

The final official results will not be out until next month.

AGENCE FRANCE-PRESSE, REUTERS