JAKARTA (Reuters) - Thailand and Cambodia agreed on Tuesday to allow civilian and unarmed military observers from Indonesia to be posted along their border, where bloody clashes over territory surrounding a centuries-old temple erupted anew earlier this month, killing at least 11 people. The agreement reached at a meeting of the Association for Southeast Asian Nations is a breakthrough for the 10-member group long derided as a talking shop. Although full details were not immediately available, Indonesian Foreign Minister Marty Natalegawa, speaking for the ASEAN, said each team would consist of 20 military and civilian members charged with observing a cease-fire agreed by both sides. "It's quite a unique regiment in the sense that Indonesian observers will be on both sides of the boundaries, on the Thai side as well as on the Cambodian side," Natalegawa told reporters after meeting ASEAN counterparts. He said the observers would report to both ASEAN and the UN Security Council. ASEAN, which prides itself on non-interference in members' internal affairs, has often appeared ineffective in resolving disputes. Fighting erupted between Thai and Cambodian forces early this month on a disputed stretch of border. at the 900-year old Preah Vihear temple. At least three Thais and eight Cambodians were killed and dozens of people wounded in the February 4-7 exchanges. Sporadic clashes have broken out since then. An international court awarded the temple to Cambodia 49 years ago but both countries lay claim to a 4.6 sq km (1.8 sq mile) patch of land near it. They have been locked in a standoff since July 2008, when Preah Vihear was granted UNESCO World Heritage status, which Thailand opposed on grounds that the land around the temple had never been demarcated. The crisis is an important test for ASEAN, which is aiming to build an EU-style community by 2015 but is riven by a host of territorial and other disputes. ASEAN includes Brunei, Cambodia, Indonesia, Laos, Malaysia, Myanmar, the Philippines, Singapore, Thailand and Vietnam. Cambodia initially asked the U.N. Security Council to deploy peacekeepers at the border and it has also asked for ASEAN observers. Thailand has called for a bilateral solution but said it welcomed ASEAN's "support. The Preah Vihear temple, known as Khao Phra Viharn in Thailand, sits on a wedge of land on an escarpment that forms a natural border overlooking northern Cambodia. The International Court of Justice in 1962 awarded the temple to Cambodia, which uses a century-old French map as the basis for its territorial claims, but the ruling failed to determine ownership of the scrub next to it.