Cambodia is gearing up for more mass rallies, with up to 50,000 people slated to attend a three-day opposition demonstration beginning Wednesday.

MPs-elect for the opposition Cambodia National Rescue Party (CNRP) are boycotting the National Assembly in protest at alleged irregularities they claim cost them victory in recent general elections. CNRP leader Sam Rainsy has demanded international intervention and also threatened a general strike. The turmoil has alreadyclaimed one life, and fears are growing of further bloodshed.

The Cambodian People’s Party (CPP) of strongman Prime Minster Hun Sen, who has held power for 33 years, won 68 out of 123 legislative seats at the ballot box on July 28. However, the opposition claims they were defrauded out of eight seats that would have swung the balance of power. “It is frustrating [not being in parliament], but we are all united behind the boycott,” says Keo Phirum, a CNRP MP-elect for Kratie province.

Not everyone agrees that the CNRP won the most votes. Ou Virak, president of the Cambodia Center for Human Rights, says that opposition politicians “should just admit that they didn’t get enough votes” and instead “emphasize there were significant irregularities.” Allegations of vote buying, intimidation and “ghost voters” swooping in to sway borderline constituencies have also not stopped international governments from tentatively recognizing Hun Sen’s victory.

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Nonetheless, discontent over land rights, deforestation, extractive industries and rampant corruption is running high, and a groundswell of opposition is developing as people sense that change may finally be possible. “It is remarkable, the absence of CPP supporters in public, on TV or radio,” says prominent political analyst Lao Mong Hay.

Even when CPP supporters are encountered, they may not be what they appear to be. TIME spoke to a group of Phnom Penh residents who said they festooned their homes with progovernment banners purely for the benefit for visiting officials, and that they really supported the opposition.

Buoyed by this unprecedented public movement, Sam Rainsy has entered negotiations with Hun Sen and reportedly demanded that his party receive the key post of National Assembly president plus six of the 12 committee-chairmen positions in exchange for taking their seats. Hun Sen has laughed off the demands (“Have you ever seen, anywhere in the world, a minority party holding the position of the president of parliament?” he asked reporters) but is clearly perturbed and has erected barricades around his official residence.

In the meantime, a game of brinkmanship continues. “There could be trouble during this week’s protests as our feedback from supporters is that we have been too soft so far,” one CNRP insider tells TIME. “If we compromise now, [our supporters] are never going to vote for us again.”

Some say that the CNRP is being pushed to take on Hun Sen by hard-line members of the Cambodian diaspora, who are among the party’s chief financial backers. The fear is that Hun Sen will respond by ordering a bloody crackdown, exacerbating the crisis further. “The government is so prone to making [those kind of] mistakes,” says Ou Virak, who calls the CNRP position “irresponsible” and urges compromise.

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In this climate, many see the need for a broker to engineer a settlement acceptable to both sides. However, the most obvious candidate, King Norodom Sihamoni, has distanced himself from the crisis and also refused a CNRP request to delay the National Assembly opening while electoral irregularities were investigated. “Compared with his father, [King Sihamoni] is so weak in so many ways,” said Lao Mong Hay. (Cambodia’s revered King Norodom Sihanouk postponed parliament in 2003 amid a comparable deadlock.)

The CNRP plans to march Wednesday with a petition to the U.N. and at least seven foreign embassies calling for international intervention. However, the city authorities have only granted permission to hold a stationary demonstration of no more than 10,000 people at Phnom Penh’s Freedom Park, citing traffic concerns and the inability to guarantee the safety of a larger crowd.

Judging by the 20,000 people who turned up to similar protests last month, there is little chance of these conditions being followed. Troops remain a fixture on the streets of the capital, and with two bitter adversaries unwilling to compromise, a country holds its breath.

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