Abhisit acknowledged that the protests have created widespread division within Thai society.
"Rebuilding the physical city is straightforward, however, the spiritual rebuilding is very hard," he said.
"Let me reassure you that this government will meet these challenges and overcome these difficulties through the five-point reconciliation plan that I had previously announced," he said.
The plan, first announced on May 3, offers political reforms and an investigation into political violence. Before the latest violence, Abhisit had offered fresh elections in November, but has since withdrawn the offer, leaving Thailand's political divisions unhealed.
The prime minister's address came after Thailand's worst political violence in 20 years earlier this week, when troops cracked down on protesters - many of them supporters of ex-PM Thaksin Shinawatra - who sought Abhisit's resignation and early elections.
At least 15 people, including a foreign journalist, were killed in the resulting violence, which also left several landmark buildings across Bangkok torched.
An eerie calm has settled over the capital two days after the crackdown.
An overnight curfew remains in force for at least two more nights, and Thai military units continue scattered military operations under a state of emergency. Police say they received a report that nine bodies were found at a shopping mall near the former protest site, but only one body has been confirmed by emergency workers.
Officials face the challenge of reassuring foreign investors and tourists that Thailand is safe.
"This has gravely shaken confidence in Thailand. What businesses need now is that the government and security forces restore law and order and existing businesses can resume their operations," Nandor von der Luehe, chairman of the Joint Foreign Chambers of Commerce of Thailand, told Reuters.
"At the same time, the government should ensure that the armed elements do not go underground and start a guerrilla war in Bangkok and around the country. If such a scenario happened, it would drive businesses away from Thailand," he said.
Thaksin previously had warned that a military crackdown can trigger a guerilla war.
"There is a theory saying a military crackdown can spread resentment and these resentful people will become guerrillas," he told the Reuters news agency by telephone.