By Kylie Morris
BBC News, Bangkok
A Thai Cabinet minister has resigned amid widespread criticism of a $1.9bn business deal involving the Prime Minister, Thaksin Shinawatra.
Mr Thaksin urged people not to join Saturday's protest rally
Culture Minister Uraiwan Thienthong said she was resigning out of concern for the ethics of good governance.
Her resignation comes in the wake of the sale by Mr Thaksin's family of shares in Shin Corp, now known in Thailand as the sale of the century.
Mr Thaksin refused to comment directly on the culture minister's resignation.
But on a visit to a city slum he vowed to keep fighting calls for his resignation and listen instead to the voices of the 19 million Thais who voted for him.
Mrs Uraiwan was no particular friend of the prime minister.
Her husband, a factional leader within the ruling party, had fallen out with Mr Thaksin, calling on MPs from the country's north-east to use their own judgement when voting in parliament rather than following the party line.
Mr Thaksin urged people not to attend an anti-government rally planned for the capital on Saturday, declaring that all they would hear was "crazy lies" from those determined to tear apart the nation.
Others have expressed concern for the safety of the public. The US embassy has warned its citizens to stay away from the protest for fear of violence.
But many Thais are expected to attend to show their concern over the deal done by Mr Thaksin's family last week to sell their nearly 50% share in the Shin Corp telecoms conglomerate to Singapore's state-owned investment firm.
Regulators have now said that Mr Thaksin's son probably did break the law by failing to disclose information about changes in his shareholdings, but the Securities and Exchange Commission said it found no evidence of insider trading.
The question now is whether that is enough to maintain people's confidence in their prime minister.