Red-shirted protesters completely surrounded the Thai Government House in Bangkok, but promised to open up access on Wednesday, when they will move to the Foreign Ministry to demand the resignation of Kasit Piromya for supporting the PAD.

Mr Abhisit Vejjajiva is refusing to be intimidated by red-shirt protesters laying siege on Thailand's Government House by saying he will defy them and walk into the building.

Mr Abhisit's determined stand caused several cabinet ministers yesterday to express nervous concerns that his presence could be seen as a challenge to the anti-government protesters who mainly support former prime minister Thaksin Shinawatra

Police and security officials would evaluate the situation today before recommending what course of action Mr Abhisit should take, sources said.

But key organiser Jatuporn Prompan of the pro-Thaksin United Front for Democracy against Dictatorship (UDD) said protesters will move on Wednesday to focus on Thailand's foreign ministry building.

The compound at Government House was completely surrounded by thousands of red-shirt protesters early on Tuesday afternoon.

Supporters of the UDD from across the country, mostly from the Northeast and the North, converged at Sanam Luang on Tuesday morning before they marched hours later to Government House in Bangkok.

Hundreds of policemen who were deployed in front of Bangkok's Government House to prevent the protesters from getting close to the premise were forced to make a retreat by the huge human wave of red-shirt protesters.

Warnings were occasionally issued by police using megaphones urging the protesters not to attempt to break into the premise or face legal actions.

Prime Minister Abhisit who is holding a cabinet meeting in Cha-Am district of Phetchaburi province has been regularly informed of the developments of the demonstration.