Bangkok  - A royalist mass movement that closed Bangkok's two airports last year and besieged parliament will regroup this week if current anti-government protests turn violent, one of their leaders said Sunday.

Protesters who want fugitive former prime minister Thaksin Shinawatra back in power claim that 100,000 people will gather Wednesday to protest the September 2006 coup that ousted him.

Suriyasai Katasila, a leader of the rival movement that supports the current government, said demands for fresh elections and the resignations of key privy counsellors were extreme and unjustified.

He said his People's Alliance for Democracy - who wear the royal yellow - are following events "on an hourly basis" and were ready to confront their rivals if Wednesday's rally gets out of control, the Nation newspaper quoted him as saying.

Natthawut Saikuea, a leader of the pro-Thaksin United Front for Democracy against Dictatorship, said Sunday his red-shirted followers will disrupt next week's summit of the Association of South-East Asian Nations if the government blocks rural supporters from coming to Bangkok for the demonstration.

Thaksin's critics say he is desperate to resolve his fugitive status, shed a two-year prison sentence for abuse of power and recover some 2 billion dollars in assets frozen by the government on suspicions that it was accumulated through corruption.

His followers plan to march on the monarchy's Privy Council chief Prem Tinsulanonda's house on Wednesday to demand his resignation for being an alleged mastermind behind the coup.

Thaksin's supporters dress in red to distinguish themselves from the yellow-clad movement that helped bring down a Thakin-backed government last year.

Some analysts say that while Thaksin is still popular with many Thais, he will find it hard to unseat a government supported by the powerful military establishment that mostly distrusts him. dpa