PHNOM PENH • A sea of pro-government supporters rallied in the Cambodian capital in support of strongman Prime Minister Hun Sen yesterday, two days before local polls are set to test the mettle of an opposition desperate to upend his 32-year rule.

Tomorrow's vote in more than 1,600 communes - or village clusters - comes after months of political tension in the fragile democracy, where Mr Hun Sen is accused of crushing dissent after nearly losing the last election in 2013.

The opposition movement has been hit hard by his crackdown and the June 4 vote is seen as a barometer for its chances of turfing Mr Hun Sen out at next year's general election. They hope to draw on frustration among Cambodia's young over graft and the shrivelling space for free expression.

In past elections, Mr Hun Sen has opted out of overt campaigning, casting himself as above the fray. But in a possible sign of nerves over the June 4 vote, he took the microphone at yesterday's parade, delivering a well-worn speech to an estimated 200,000 supporters about the stability he has brought to Cambodia.

"Which party brought about peace?" he asked the raucous crowd decked out in shirts, hats and flags bearing the emblem of his Cambodian People's Party (CPP).

"If the CPP had not toppled Pol Pot, would Pol Pot have given up power and stopped killing us?" he asked, referring to the Khmer Rouge leader who oversaw the killing of up to two million Cambodians in the late 1970s. Mr Hun Sen,64, himself a Khmer Rouge commander, later defected and joined the Vietnam-backed government that ousted the brutal regime.

"This is the choice between peace and security for development, and chaotic destruction," he said.

Since Mr Hun Sen came to power, Cambodia has emerged from decades of conflict to clock annual growth rates above 7 per cent, a record he highlighted.

But the opposition Cambodia National Rescue Party, which held its own rally on the other side of town yesterday, has gained ground in recent years.

The party nearly unseated the premier in 2013 and claims it lost only due to voter fraud.

The movement has been dented by Mr Hun Sen's subsequent crackdown, with at least 27 Cambodian human rights defenders and political activists thrown behind bars since 2013, according a recent Amnesty International report.

AGENCE FRANCE-PRESSE, REUTERS