PHNOM PENH, Cambodia (AP) -- Long-serving Cambodian strongman Hun Sen began another five-year term as prime minister Tuesday, declaring his victory "historic" despite accusations of rigged elections, mass protests and a boycott of parliament by the opposition.
Ruling party lawmakers renamed Hun Sen as prime minister of the Southeast Asian nation in a parliamentary vote that was boycotted by the opposition. Hun Sen, who has ruled virtually unchallenged for nearly three decades, took the oath of office with fellow Cabinet members in front of King Norodom Sihamoni at the Royal Palace later in the day.
The opposition's 55 elected lawmakers stayed away from parliament's opening session Monday and again Tuesday over allegations the country's disputed July ballot was marred by fraud, while the ruling Cambodian People's Party's 68 lawmakers renamed Hun Sen to his post.
Opposition leader Sam Rainsy said he would announce the party's next step on Wednesday but called Hun Sen's re-appointment a "constitutional coup."
Speaking before the half-empty National Assembly, Hun Sen displayed his characteristic confidence and dismissed allegations of cheating.
"Today is a historic day for Cambodia," Hun Sen said in his acceptance speech. "The election results are a reflection of the full support we have from the majority of Cambodians."
The July 28 vote, he added, was a "free, fair, just and transparent election."
Hun Sen's party performed unexpectedly weakly in the election, emerging with its poorest results in more than a decade to see its majority wither in the 123-seat National Assembly. The opposition, running on a newly unified slate, meanwhile boosted its number of elected lawmakers to 55 from 29.
The result emboldened the opposition, which has staged several protests that drew tens of thousands of supporters who backed its call for an independent probe of election irregularities.
Experts say that a stronger and more vocal opposition could lead Hun Sen to make some changes in the government and small political compromises but it is unlikely to loosen his grip on power.
"This is a huge wake-up call (for Hun Sen's government) ... and now they all acknowledge that they all need to reform," said Ou Virak, president of the Cambodian Center for Human Rights. "But the question is, are they able to reform?"
Hun Sen and opposition leader Sam Rainsy have held three rounds of talks this month in an effort to resolve the political deadlock. Hun Sen told reporters Tuesday he was ready to talk again -- but only if opposition lawmakers take their seats in parliament.
"Before resuming negotiations, you have to first take an oath," Hun Sen said in comments directed at the opposition, adding that the opposition's decision not to attend parliament was its own and the legislature's doors remained open.
He said the ruling party was considering offering several senior posts to the opposition, including vice president of the legislature and that the government "is determined to undertake thorough reforms in all fields."
On Tuesday, Sam Rainsy called the convening of parliament without the opposition -- and Hun Sen's return to power -- a violation of the constitution.
"They have actually lost the election," Rainsy told The Associated Press. "They refuse any investigation into irregularities, which means they know that any serious investigation would show they have lost... This is a constitutional coup that we condemn."
Hun Sen's power remains rock-solid for now, leaving the next move up to the opposition. Having raised the expectations of their supporters -- who showed their faith by coming out in the streets despite the threat of violent repression -- the Cambodia National Rescue Party must decide if their confrontational approach risks bringing diminishing returns.
But striking a compromise with Hun Sen's government could lose them the momentum they gained through their spirited street rallies, said Lao Mong Hay, an independent political analyst.
"The opposition has been riding on the waves of the people" who are not interested in a political compromise, he said, adding that the turnout for the opposition was less an expression of support for their policies and more a "protest against the establishment."
Cambodians now have aspirations including hopes for social advancement, greater equality, and an end to corruption, land grabbing and deforestation, all of which have not been addressed by Hun Sen's regime, Lao Mong Hay said.
Hun Sen's past record of dealing harshly with opponents remains another factor.
At least one person died and 10 were injured when security forces cracked down on opposition protests earlier this month.
And on Sunday, security forces backed by thugs broke up a peaceful opposition protest at a Buddhist temple compound in the capital, wielding stun guns, electric batons and slingshots that left about 10 people injured, said Rupert Abbott of Amnesty International.
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