Thousands of supporters of deposed Thai Prime Minister Thaksin Shinawatra have held a rally in the capital, Bangkok, calling for fresh elections.
Mr Thaksin addressed them by video-link, describing democracy in Thailand as weak and unstable.
His supporters are also calling for the return of the Thai constitution that existed before a military coup three years ago.
Mr Thaksin was ousted in the coup and has been living in exile ever since.
In his absence, he has been sentenced to a two-year jail term in a conflict of interest case.
Police said up to 20,000 people attended the rally by red-shirted supporters of the United Front for Democracy Against Dictatorship (UDD) at Bangkok’s Democracy Monument.
Thursday is a public holiday in Thailand to mark Constitution Day.
“In Thailand, democracy is weakened and politics is unstable,” said Mr Thaksin, speaking from an undisclosed location.
“Return democracy, justice and prosperity to the people,” he added.