ASEAN ministers failed to ease tensions between member states Thailand and Cambodia during crisis talks on Tuesday over an escalating standoff at a disputed historic site, diplomats said.

'Both ministers from Thailand and Cambodia basically gave briefings on the issue,' an Asian diplomat said after the unscheduled lunch meeting during annual Asean ministerial talks.

'Cambodia wants it resolved through Asean but the Thai side wants it resolved bilaterally,' he added.

Envoys said Cambodia had sent a letter to the Association of Southeast Asian Nations (Asean) this week requesting help to resolve the dispute with Thailand over a section of border near ruins of an 11th-century Hindu temple.

The row, the latest flare-up in a long-running feud which stirs nationalist passions in both countries, escalated on Tuesday when Phnom Penh requested an emergency meeting of the UN Security Council to 'avoid armed confrontation.' Asean Secretary-General Surin Pitsuwan said after the lunch meeting that the atmosphere had been 'friendly' but he gave no indication progress had been made.

'Asean still insisted on the statement that the chairman put out Sunday evening that expects the two sides to find amicable solutions to the issues between them,' he said.

'Asean still stands ready to (give) any support that the two sides want Asean to play. We can't go any further than that.' Asean said on Sunday it had received assurances from both countries that they would show 'utmost restraint' as hundreds of troops from each side were deployed to the disputed area.