Anti-government demonstrators in Thailand said Saturday they will not take over Bangkok's airports — as protesters did last year — but they will exert mounting pressure until the prime minister steps down.

Several thousand protesters surrounded the office of Prime Minister Abhisit Vejjajiva for a third day, though the numbers had dwindled from a high of about 30,000 on Thursday.

"We will stay indefinitely," said a protest leader, Nattawut Sai-kua, adding that protests will also branch out to other locations that he declined to name. "Our strategy is to keep applying pressure. The strategy will be adapted daily."

The demonstrators are supporters of former Prime Minister Thaksin Shinawatra, who was ousted by a military coup in 2006 for alleged corruption and abuse of power. They say Abhisit's government came to power illegitimately three months ago and should step aside so new elections can be held. Abhisit has rejected their calls.

This week's protests are the latest episode in Thailand's long-running political turmoil, which has become a tug-of-war between Thaksin's supporters and opponents. Each is known by the color of shirts they wear at rallies, red for pro-Thaksin and yellow for anti-Thaksin.

Yellow-clad protesters dominated last year's protests — the first to camp at Government House where they stayed for three months. They are credited with bringing down two governments run by Thaksin's allies, and their protest culminated in a weeklong siege of Bangkok's two airports in December, crippling the vital tourism industry at the start of the holiday season.

"We're not going to seize the airports," Nattawut said. "We're not breaking into the Government House or destroying any public property."

Abhisit was named prime minister by Parliament in December after courts removed the two earlier pro-Thaksin administrations. The stately Government House had been pillaged by protesters and its manicured grounds ripped apart by their three-month sit-in.

Thaksin's supporters say the rulings were politically motivated and biased against Thaksin.

Thaksin fled into exile last year and has been convicted in absentia of violating a conflict of interest law.

The former prime minister has become a fixture at his supporter's rallies, speaking via video link from overseas. He has surfaced in numerous countries around Asia, the Middle East, Latin America, and on Friday night spoke from Africa.

Thaksin publicly accused the chief adviser to King Bhumibol Adulyadej, the country's revered constitutional monarch, of being a mastermind of events that led to the 2006 coup. It was an accusation he has repeatedly alluded to without naming Privy Council head Prem Tinsulanonda, a retired army general who served as prime minister in the 1980s.

"Do not drag the monarchy down," Thaksin said, accusing Prem and others of undermining democracy in Thailand. "Political involvement by the Privy Council is very inappropriate because it makes people question the king's role in politics."

Thaksin echoed his supporters' calls to dissolve Parliament and hold fresh elections.

"We want to see true democracy in Thailand. We want to see justice," Thaksin said.

Abhisit avoided his office Friday but says he plans to return Monday.

"Whether to resign or not resign is a political matter within the system," Abhisit told reporters Friday at his Democrat Party's headquarters. "Right now, the situation remains normal. We are still operating normally."