Bangkok was quiet for a second day Friday after a military assault on Red Shirt opposition protesters. A curfew imposed overnight Wednesday was extended to Saturday after rioters burned key buildings following a Red Shirt decision to surrender.
More than 40 people have died since last week in clashes with security forces, including a breakaway general who was assassinated during a media interview.
Catherine Ashton, high representative of the European Union for foreign affairs and security policy, said Friday she was "deeply saddened" by the death toll from the Thai unrest.
"The violence has solved nothing, but only harmed Thailand and its people, by deepening divisions rather than healing them," she added. "National reconciliation is now an absolute necessity."
Thai Prime Minister Abhisit Vejjajiva said in a televised address Friday that he would work to bring stability to the country, the Bangkok Post reports.
"You can be assured that this government has every intention of moving the country forward, restoring order, making sure that our recovery is well on track, and that we will do so in a transparent manner," he said.
Thai officials said, meanwhile, that they were worried opposition forces would go underground, warning police to remain vigilant.
"I hope that the Thai nation will look ahead and seek a pragmatic solution," Ashton added.