A Thai court has blocked government plans to part-privatise state power firm EGAT, dealing a fresh blow to Prime Minister Thaksin Shinawatra.
Critics of the planned sale were ecstatic at their legal victory
The Supreme Administrative Court said the planned sale was illegal, as it would mean transferring land bought as a state enterprise to a private firm.
Critics of the deal said shares would be sold to government supporters and that prices would rise as a result.
The sale was seen as a key test of Mr Thaksin's privatisation programme.
The prime minister is under huge pressure, amid allegations of corruption and claims of a conflict of interest, following the sale of his family's stake in Shin Corp earlier this year.
He has called a snap election for 2 April, but this has prompted widespread calls for his resignation, while opposition parties have threatened to boycott the poll.
The flotation of the Electricity Generating Authority of Thailand was suspended last year after consumer groups and anti-privatisation activists petitioned the court.
The proposed sale would have raised up to $895m.