In Thailand, tens of thousands of demonstrators have staged a mass rally outside the offices of Prime Minister Thaksin Shinawatra and say they will not leave until he resigns. The protest has been peaceful, but the prime minister has warned he is prepared to declare an emergency if violence breaks out.

The protesters marched to government house in central Bangkok shortly after dawn Tuesday after an all night rally.

The protesters are demanding Prime Minister Thaksin Shinawatra resign so an interim appointed government could revise the constitution and organize new elections.

They accuse the Thaksin government of corruption and abuse of office and vow to keep their vigil at government house until he steps down.

Mr. Thaksin, campaigning in northeast Thailand, is refusing to resign. The prime minister says he wants a political compromise and wants to avoid violence. But he is prepared to declare an emergency if peace is not kept.

Bangkok's 20,000-strong police force was put on alert, with hundreds deployed around government house.

The prime minister has faced rising protests since his family sold two billion dollars of shares in a company he founded and legally avoided taxes.

Mr. Thaksin - who was reelected last year in a landslide - says the street protests are an undemocratic way to try to oust him.

The prime minister has tried to diffuse the growing pressure by dissolving parliament and calling snap elections on April 2. However, the three main opposition parties are boycotting the vote saying it cannot be fair if held under the current government.

A professor at Bangkok's Chulalongkorn University, Thitinan Pongsudhirak, says the situation has become untenable and either the prime minister must resign or emergency measures will be declared.

"We have a very dicey situation here. Something will have to give," he said. "The anti-Thaksin people are not going away. Thaksin seems to want to fight to the bitter end. But it's untenable to have a besiegement of government house like this." He says the prospects for a compromise appear distant because the positions of both sides have hardened in recent weeks.

Mr. Thaksin continues to enjoy widespread support among rural people and the poor and he brought together an estimated 100,000 of these people at his own rally 10 days ago.