Thailand's new prime minister Abhisit Vejjajiva was forced today to relocate his maiden policy speech after riot police failed to clear protesters besieging Bangkok's parliament building.

Democrat Party leader Abhisit, who was elected in a parliamentary vote about two weeks ago, instead addressed lawmakers at the foreign ministry as protracted political turmoil in the kingdom showed no sign of ending.

"The urgent measures in the first year are restoring confidence and stimulating the economy," Abhisit said.

Despite repeated efforts by hundreds of riot police armed with shields to push open the gates and create a path for MPs to enter parliament, more than 2,000 red-shirted protesters calling for new elections had refused to budge.

They are loyal to Thaksin Shinawatra, the premier ousted in a 2006 coup, and say Abhisit's government is not legitimate as he came to power after the Thaksin-linked former ruling party was dissolved by a court early this month.

"The government intended to deliver a policy statement but this was prevented by protesters," said Satit Wonghnongtaey, a minister attached to the prime minister's office.

Oxford-educated Abhisit's election ended six months of increasingly disruptive protests by anti-Thaksin group the People's Alliance for Democracy (PAD) which peaked when they seized and shuttered Bangkok's two airports.

The yellow-clad PAD said the ruling People Power Party (PPP) was simply a puppet for twice-elected Thaksin, who was toppled in a coup in 2006 and lives abroad to avoid being jailed on a corruption conviction.

The week-long closure of the airports in November and early December caused massive economic damage, and Abhisit must give his policy speech before his government can start tackling the nation's political, economic and social woes.

Thailand remains deeply divided between supporters of Thaksin and elements of the old power cliques in the military, palace and bureaucracy who felt threatened by his immense popularity with the rural poor.

Fears of a repeat of clashes

Supporters of Thaksin, meanwhile, said the dissolution of the PPP on Dec 2 was a "disguised coup" and want parliament dissolved.

They began gathering Sunday and about 9,000 of them sealed off parliament on Monday, forcing repeated delays of Abhisit's policy statement. Police said the numbers had dwindled to about 2,300 by Tuesday morning.

Lieutenant General Suchart Muenkaow, commander of the metropolitan police force, said about 3,750 police were on duty to oversee the demonstrators, but added that they would not prevent protesters moving to the foreign ministry.

"Police will let everything go naturally, and they are unarmed except for shields and batons," he said.

An AFP correspondent at the scene said about 100 unarmed soldiers were also standing guard outside the ministry, as Abhisit waited for coalition lawmakers to arrive.

Suthep Thaugsuban, deputy prime minister and Democrat Party secretary general, said earlier that authorities would not use force.

"We merely want to open the way for MPs to attend the meeting but we still adhere to our principle not to use force, arms or teargas," he told a Thai television station.

Authorities are keen to prevent a repeat of clashes outside parliament on Oct 7, when two people were killed and nearly 500 injured as the PAD tried to prevent then-premier Somchai Wongsawat giving his maiden policy speech.

Abhisit, 44, became Thailand's third premier in four months after a court dissolved the PPP.

He rose to become prime minister with the help of defectors from the PPP and coalition parties previously allied with it.