PHNOM PENH, Cambodia (AP) -- Cambodia's longtime authoritarian leader 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, will take the oath of office 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. The ruling 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 ruling Cambodian People's Party took a surprise hit at the election, emerging with its weakest results in more than a decade. Its majority withered to 68 out of 123 National Assembly seats, while the opposition secured 55 seats, up from the 29 it previously held.
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.
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."
"He's going to have to make some calibrations," said Cambodia historian David Chandler, emeritus professor of history at Australia's Monash University. But he added, "The system is going to remain the same because it benefits the people who run the country, the people who have money."
The opposition is now left with dwindling options, Chandler said.
"One is to go back on what they said (and end the boycott) and the second is just to let Hun Sen run the country the way he wants," said Cambodia."
Another option: "They could take to the streets, but that's very dangerous" because of the threat of bloodshed, he said.
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.
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 reporters. "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."
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