Colombo: Sri Lanka's main Opposition which had hopes of manoeuvring itself back into power was on August 16, battling an unexpected internal rift as international support mounted for the government's peace drive.

President Chandrika Kumaratunga's People's Alliance (PA), which is the main Parliamentary Opposition in the co-habitation government, saw a senior member openly challenging the leadership, party sources said.

They said former minister Jeyaraj Fernandopulle questioned Kumaratunga's integrity at a meeting on August 15, while a section of the party was in talks with Prime Minister Ranil Wickremesinghe about crossing over to government ranks.

Until on August 15, it was the government that appeared unstable, with PA spokesman Sarath Amunugama vowing to muster a majority in the 225-member Parliament and form a government amid allegations of a "coup."

"We will form a government when we have the 113 MPs (for a simple majority). We have plans for it, but we will not disclose our strategy," Amunugama said earlier this week.

However, with the rebel Liberation Tigers of Tamil Elam (LTTE) and the government agreeing on a timetable to open formal peace talks in Thailand, the Prime Minister has emerged stronger, diplomats said.

Britain, the United States and Japan have welcomed the talks scheduled to take place between September 12 and 17 at a neutral venue in Thailand while Western diplomats said there was widespread support for the start of the negotiating process.

Norway clinched a deal to start the face-to-face talks three years after it assumed the role of a "facilitator" acceptable to both parties.

Government spokesman G L Peiris has said Constitutional Amendments will be moved before the end of August to clip some of President Kumaratunga's powers to sack the Parliament and to give legislators a conscience vote.

The conscience vote amounts to a de facto suspension of the anti-defection provisions in the 1978 Constitution and will help the ruling United National Party (UNP) to win over Opposition MPs.

Any deal reached with the Tigers requires Parliamentary approval with a two-thirds majority in the 225-member Assembly, and with the current composition, the ruling UNP needs the support of at least another 20 MPs.

Peiris, who is also Constitutional Affairs Minister, said the government was confident of winning sufficient numbers to have the mandatory two-thirds majority to amend the Constitution.

Government sources said attempts to bring about a truce between the hostile President and Parliament had failed and the wrangling could lead to splits in the Opposition.

Opposition leader Mahinda Rajapkse is openly clashing with several close confidants of President Kumaratunga who have been pushing for an early ouster of the government, which won a six-year term at the December 2001 elections.

With a two-thirds majority, the government could also move to impeach Kumaratunga, who was elected at a separate vote in December 1999. Her term would otherwise end in December 2005.

Under the 1978 Constitution, the President is empowered to sack Parliament without giving any reason as soon as the Assembly completes one year of its six-year term.

Kumaratunga tried to give an assurance to her own supporters on August 15 that she will not sack the Assembly, but her legislators rejected the assurance, a party source said.

He said Kumaratunga had given a similar assurance but went back on it in October 2001 when she dissolved Parliament after her party lost its majority following a flood of defections to Wickremesinghe's UNP, which won the subsequent elections.