Updated

Thousands of opposition supporters marched through the Cambodian capital Sunday vowing to rally for several days in a renewed bid to overturn Prime Minister Hun Sen's disputed election win.

The protest, called by the Cambodia National Rescue Party, comes a day after a rare meeting between opposition chief Sam Rainsy and the strongman premier to break the political paralysis gripping the kingdom.

Hosted by King Norodom Sihamoni the meeting made limited progress towards ending the stalemate since the July polls, which returned the Cambodian People's Party to power despite allegations of widespread vote-rigging.

But it was not enough to stop Sunday's planned protest, which saw CNRP supporters led by Rainsy march ten kilometres (6 miles)through Phnom Penh from their party headquarters to a rally in Democracy Park.

Around 20,000 people converged on the park, according to an AFP reporter, their numbers boosted by arrivals from the provinces.

Holding up banners reading 'my vote, my nation' and 'where is my vote?' -- in a reference to the alleged poll fraud which saw the CPP win 68 seats to 55 for the CNRP -- many protesters also carried backpacks apparently braced for a long stay.

"Brothers, this is an important mission to rescue the nation," Rainsy said addressing the rally, adding the alleged fraud meant his party "cannot accept the results."

Rainsy again called for a recount or new vote and stated that opposition lawmakers will not attend the opening of the parliament on September 23 but will attend new talks on Monday with the CPP.

But "there will be no talks on power sharing" he warned, without the alleged election irregularities being cleared up.

Anti-riot and military police were deployed at key locations in Phnom Penh on Sunday, according to an AFP reporter, but security forces kept a low profile at the rally site.

Ahead of the rally the government set a limit on the number of protesters at 10,000 and said it must finish by nightfall on Sunday.

But protesters remained defiant, vowing to stay in the park until their demands are met.

"Our votes were robbed," said 56-year-old Srin Chea, who travelled from southern Kandal province.

"I am angry. I want justice. I am not afraid of death."

Rainsy described Saturday's meeting with Hun Sen -- in which the pair shook hands for the television cameras -- as a step towards breaking the country's political deadlock, but it did not end his party's rejection of the poll result.

So far the CNRP's efforts to challenge the outcome have failed and it has few options left in its bid to overturn Hun Sen's victory.

Hun Sen, 61, has been in power for 28 years and has vowed to rule until he is 74.

A former Khmer Rouge cadre who defected and oversaw Cambodia's rise from the ashes of war, his government is regularly accused of ignoring human rights and suppressing political dissent.