Ousted Thai PM Thaksin Shinawatra has called for fresh elections in a video address shown to supporters in Bangkok.
Mr Thaksin was ousted in a bloodless coup in September 2006
It is only the second time the deposed PM's voice has been heard in the country since his fall from power.
"Now it is time to go ahead with a new election to bring democracy back," Mr Thaksin told the crowd, which police estimates put at 15,000 people.
Mr Thaksin was ousted last year. Supporters have staged nightly rallies since a ban on his party last month.
The military government has said it plans to hold elections this December.
Mr Thaksin taped the address in London, where he lives.
Police said as many as 15,000 pro-Thaksin supporters turned up
"Please speed up the new elections and turn the country back to democracy," Mr Thaksin said.
"It is time for reconciliation and to move forward with elections. That is the best solution for the country."
In May, a court ordered Mr Thaksin's Thai Rak Thai party be dissolved because of electoral violations.
This week, the committee set up to examine corruption claims against Mr Thaksin said it had concluded that he had "committed wrongdoings".
It issued two orders freezing his assets, including 21 accounts holding money made from the controversial sale in January 2006 of Shin Corp, his telecoms giant, to a Singaporean firm.