Bangkok - A fleet of 100 private buses went on strike Thursday outside the Thai Transport Ministry, adding to Bangkok's already notorious traffic, to protest a freeze on bus fare hikes in tandem with rising oil prices.

"If the government won't let us raise the fare, we want them to subsidize our diesel prices at 10 baht [32 cents] a litre," said Chaichat Chaiwiset, president of the Private Bus Operators Association.

Chaichat has threatened to extend the strike to include all 8,000 of the association's buses if the government refuses to comply with the group's demands.

Diesel prices hit 40 baht a litre at some petrol stations Thursday, surpassing the price of benzine for the first time in decades.

Thailand's Central Administrative Court on Wednesday ordered an injunction barring city buses, private and public, from raising their fares.

While buses belonging to the Bangkok Mass Transit Authority, the state enterprise that operates thousands of buses in the capital, has complied with the court order, private bus operators have strongly opposed the move because it would further cut into their meagre profits.

Bangkok is served by a confusing mix of public and privately owned buses. The private buses, while providing a service, are often criticized by the public for reckless driving and using exhaust-belching vehicles. (dpa)