"I want to stress that there is no re-election, no one dissolves the legislature and also there is no mechanism to hold new election before its term ends," Hun Sen said in dismissing demands made by leaders of the opposition Cambodia National Rescue Party.
Hun Sen, who has been in power for nearly three decades, also said he became prime minister by constitutional means and would only leave the premiership by constitutional means.
Sam Rainsy, president of the CNRP, and his deputy Kem Sokha have repeatedly called for an end to his rule and for a new election while leading nonviolent rallies in the capital for nearly a week.
They plan to organize an even bigger demonstration and to block some roads in the later stages if their demands fall on deaf ears.
The CNRP claims that the July 28 general election was rigged by Hun Sen's Cambodian People's Party. The CPP won 68 seats out of the 123 in the National Assembly, with the remaining 55 going to the CNRP.