Bangkok: Thai Prime Minister Samak Sundaravej shrugged off doubts about the stability of his five-month-old government yesterday, a day after two court rulings fuelled speculation of new elections or even a coup.

Tuesday's decisions piled more pressure on the six-party coalition government, already weakened by a prolonged street campaign which has unsettled investors, but Samak declined to say how he would counter fresh moves by his opponents to oust him.

"I am listening to all the criticism and will tell the people what I think on my Sunday TV show," Samak told reporters.

The opposition Democrat Party and several senators said they would file separate petitions to impeach the cabinet after a Thai court said the government's support for a Cambodian bid to list a 900-year-old temple as a World Heritage site was illegal.

Opponents of ousted Thai prime minister Thaksin Shinawatra have whipped up a nationalist frenzy over the Preah Vihear temple, which many Thais believe belongs to Thailand, to try to kick out the pro-Thaksin government elected in December.

Also on Tuesday, a top leader of Samak's People Power Party (PPP) was found guilty of vote buying in the December poll and banned from politics for five years, a ruling that could lead to the dissolution of the main coalition party.

The legal defeats will force the government to focus on its political survival at a precarious time for the economy, as it faces soaring inflation and stuttering growth, analysts said.

The main stock index edged lower in afternoon trade as Thailand's army commander denied the latest coup rumours.

General Anupong Paochinda dismissed newspaper reports that the government may ask its army allies to launch a coup to tear up the 2007 military-designed constitution which has strengthened the courts' oversight of politicians.

"A coup won't be any good for the country," said Anupong, who took part in the putsch against Thaksin in 2006.