Bangkok  - Brushing off bomb attacks on his followers and mounting damages done to the country, a core leader of the People's Alliance for Democracy (PAD) vowed Sunday to remain at Bangkok's airports until they were victorious in toppling the government.

PAD leader Chamlong Srimuang told supporters at Government House, the site of a grenade attack early Sunday that injured 46 PAD members, that the political standoff between the demonstrators and government would have a "victor" on Tuesday.

Thailand's Constitution Court is expected to rule on Tuesday on whether the ruling People Power Party committed fraud during the December 23, 2007 elections.

A guilty verdict would lead to the dissolution of the PPP, which leads the current government, and the banning of its top executives from office. That would require Prime Minister Somchai Wongsawat to lose his post, which the PAD would claim as a victory.

In the ensuing confusion, it is expected that the PAD and its political supporters would push for an appointed interim cabinet, set up by the Constitution Court.

"The PAD and Constitution Court are functioning in parallel," said Chaturon Chaisaeng, a former politician with close ties to the current government. "Their aims will merge on Tuesday."

The PAD, a loose coalition of groups adamantly opposed to the return to power of fugitive former premier Thaksin Shinawatra, has been holding protests against the government for the past six months.

It launched its "final battle" last week, invading Suvarnabhumi International Airport on Tuesday, forcing the facility to close down completely by Wednesday, and taking over Don Mueang, the capital's former airport, the following day.

Bangkok has been completely shut off to air traffic since Thursday, causing millions of dollars in daily losses and inestimable longer-term damage to the economy.

The kingdom's two main foreign exchange earners, exports and tourism, are highly reliant on Suvarnabhumi.

Although Somchai placed both airports under emergency decree on Thursday, and ordered the police to clear out the demonstrators, the authorities have thus far refused to act.

The police are aware that Somchai may no longer be prime minister by Tuesday, and recall that they came under heavy criticism from the Thai public for an October 7 crackdown on the PAD that left two demonstrators dead.

Thai Queen Sirikit, wife of Thailand's much-revered King Bhumibol Adulyadej, attended the funeral of one of the October 7 victims.

Besides broad backing from Bangkok's middle class, the PAD is known to have the support of many members of Thailand's political elite, including the army.

While Thai authorities have yet to take action against the PAD, there are growing concerns that pro-government demonstrators will prove less conciliatory.

The pro-government Democratic Alliance Against Dictatorship (DAAD) planned a mass rally Sunday night in Bangkok.

There are fears that the DAAD, which has been law-abiding thus far, will turn to violence in the coming days to rein in the PAD.

"Thailand is tipping out of control," warned Thitinan Pongsudhirak, a political scientist at Bangkok's prestigious Chulalongkorn University. "The DAAD could go on it's own rampage, and then who will stop them? Only Thaksin."

Thaksin, a billionaire former telecommunications tycoon turned populist politician who dominated Thai politics during two terms as premier between 2001-06, is currently a fugitive, living in self-exile to avoid a prison sentence for corruption.

But he remains the central character in Thailand's unfolding political drama.

Although banned from politics by a court ruling in May 2007, after being ousted by a coup in 2006, Thaksin has vowed to make a political comeback.

On October 21, the Supreme Court for Political Office Holders sentenced Thaksin to two years in jail for abuse of power. He claimed the verdict was politically motivated.

Thaksin is known to be the main financier behind the ruling People Power Party. Prime Minister Somchai is his brother-in-law.

The PAD's main goal has been to keep Thaksin from returning to power but some fear the movement is actually paving the way for his comeback, by creating political chaos and devastating the economy.

"The PAD, ironically, is playing into Thaksin's hands," Thitinan said. (dpa)