Thousands of Thai anti-government protesters massed ahead of a major rally Sunday aimed at suspending democracy, paralysing parts of central Bangkok a day after the main opposition party declared a boycott of snap polls.

At least 1,000 people mainly women also gathered early Sunday outside Prime Minister Yingluck Shinawatra's suburban house amid tight security, according to an AFP reporter at the scene, with thousands more expected.

The premier, who was forced to dissolve the house in early December after the Democrat Party resigned en masse from parliament, is in the north-east of the country, the heartland of her ruling party.

Demonstrators want to rid Thailand of Yingluck and the influence of her Dubai-based brother Thaksin -- an ousted billionaire ex-premier who is despised by a coalition of the southern Thai poor, Bangkok middle classes and elite.

Firebrand protest leader Suthep Thaugsuban, who has vowed to destroy the "Thaksin regime", dismisses Yingluck's call for an election on February 2, saying it will install another Thaksin-allied government.

Instead the self-proclaimed People's Democratic Reform Committee is calling for an unelected "people's council" to be installed to oversee sweeping reforms before new elections in a year to 18 months.

His movement was bolstered Saturday by the Democrats' announcement of a poll boycott.

The move dismayed the prime minister who said elections must take place to secure Thailand's fragile democracy.

"If we don't hold on to the democratic system, what should we hold on to?" she told reporters Sunday.

"If you don't accept this government, please accept the system," she said, adding elections will allow protesters to be heard at the ballot box.

Suthep began a march to the commercial heart of Bangkok joined by several thousand followers, many blowing whistles -- the symbol of the weeks-long protests -- and waving Thai flags.

Opposition protesters are expected to converge for a major rally in central Bangkok around 1100 GMT. Previous such rallies have attracted at least 150,000 people.

Demonstrators blocked traffic at several points in the capital, including at a symbolic intersection occupied by rival "Red Shirts" in 2010 pro-Thaksin rallies which ended in bloodshed.

Suthep, then deputy prime minister for the Democrat Party, faces murder charges over the crackdown which left scores dead.

Democrat leader Abhisit Vejjajiva -- who has also been indicted for murder over the crackdown -- on Saturday said his party would boycott February polls.

The Democrats have not won an elected majority in some two decades.

Their party previously boycotted elections in 2006, helping to create the political vacuum which heralded a military coup that ousted Thaksin.

Analysts say the current boycott could engineer a similar outcome, but also carries major risk for the country's oldest political party which could face a wipe out if the polls go ahead.

The PDRC has appealed for the support of the army to upend the government -- which is holding out despite enormous pressure on the streets.

But the military has indicated it will not step in directly at this stage.

Thailand has seen 18 successful or attempted coups since 1932.

Thaksin is adored among rural communities and the working class, particularly in the north and northeast, but the billionaire tycoon-turned-politician is reviled by the elite, who see him as corrupt and a threat to the monarchy.

Pro-Thaksin parties have won every election since 2001, most recently with a landslide victory under Yingluck two years ago.