Cambodia and Thailand share land border of 803 Km. The border was demarcated in the early 20th centuries when Cambodia was under the French Protectorate. The border maps were drawn in accordance with the Franco-Siam agreements in 1904 and 1907. Preah Vihear temple and its surrounding areas were the contentious border dispute between the two countries after Cambodia got independence from France in 1953. In 1954, Thai invaded Cambodia by occupying the Preah Vihear temple and its vicinity. In reaction, Cambodia brought the case to the International Court of Justice (ICJ). The then ICJ’s judgement on the case concerning the Preah Vihear temple on 15 June 1962 stated that (1) the Temple of Preah Vihear is situated in territory under the sovereignty of Cambodia; (2) Thailand is under an obligation to withdraw any military or police forces, or other guards or keepers, stationed by her at the Temple, or in its vicinity on Cambodian territory; (3) Thailand is under an obligation to restore to Cambodia any objects of the kind specified in Cambodia’s fifth Submission which may, since the date of the occupation of the Temple by Thailand in 1954, have been removed from the Temple or the Temple area by the Thai authorities.
However, 46 years later, the dispute in the same areas erupted again in 2008. It was mainly driven by the domestic political polarization in Thailand and increasing nationalistic sentiments in both countries. On 15 July 2008, Thai soldiers moved into the Keo Sikha Kiri Svara pagoda. The tensions had increased since then. Both sides reinforced their troops and heavy weapons to the border areas. Thousands of protesters belonging to the anti-Thai government People’s Alliance for Democracy (PAD) took to the street to protest against the government after Cambodia listed the temple into the list of the UNESCO’s World Heritage Site in early July.
Both sides had tried to use bilateral mechanism to contain and manage the conflict. There were frequent meetings between the foreign ministers and defence ministers of both countries in order to build trust and mutual understanding to avoid conflict. However, it failed to produce any expected outcome. Within such context, Cambodia approached ASEAN and the United Nations for an appropriate intervention in order to maintain peace and stability in the region.
At the ASEAN Regional Forum (ARF) meeting in July 2008, Cambodia requested ASEAN to take measures to prevent conflict between the two countries. Cambodia hoped that under the confidence building measures and preventive diplomacy developed and inspired by the ARF, the bilateral disputes between the two countries could have been peacefully managed. However, ASEAN did not take any action concerning the request due to the opposition from Thailand. The principle of non-interference into its member states was the structural constraint of ASEAN.
Both bilateral and multilateral efforts failed to prevent an open armed conflict between the two countries. On October 3, 2008, the troops from both sides exchanged fire near the temple. Then the armed clashes consequently and continuously took place on 15 October 2008, 3 April 2009, 24 January 2010, 25 January 2010, 30 January 2010, 31 January 2010, 16 April 2010, 4 to 7 February 2011, 15 to 16 February 2011, and 22 April from 3 May 2011. The clashes and skirmishes reportedly led to 36 soldiers and five civilians killed, and more than 200 soldiers and civilians wounded from both sides. Moreover, it displaced thousands of people, damaged infrastructure such as roads, schools, markets, and houses.
On 9 February 2011, Cambodian PM Hun Sen called for an urgent intervention from a third party to prevent the escalation of the armed conflict. He stated, “There will be no more bilateral talks, and all negotiations will be participated by the third party”. In late February, due to the efforts from Cambodia to internationalize the conflict, ASEAN under the Indonesian chair started to intervene. As a result, both Cambodia and Thailand agreed to accept 40 civilian observers from ASEAN to monitor the situation and maintain the ceasefire at the disputed border areas. Moreover, the United Nations Security Council (UNSC) also issued a statement to encourage ASEAN to play its role in maintaining peace and stability in the region.
To solve the dispute completely, on 28 April 2011, Cambodia filed a request for interpretation of the 1962 judgment, as well as a request for the indication of provisional measures, in the Registry of the International Court of Justice, referring to Article 60 of the Statute and Article 98 of the Rules of Court. It put five submissions (1) To adjudge and declare that the map in the Dangrek sector [Annex I to the Memorial of Cambodia] was drawn up and published in the name and on behalf of the Mixed Delimitation Commission set up by the treaty of 13 February 1904, that it sets forth the decisions taken by the said commission and that, by reason of that fact and also of the subsequent agreements and conduct of the parties, it presents a treaty character; (2) To adjudge and declare that the frontier line between Cambodia and Thailand, in the disputed region in the neighbourhood of the temple of Preah Vihear, is that which is marked on the map of the Commission of Delimitation between Indo-China and Siam [Annex I to the Memorial of Cambodia]; (3) To adjudge and declare that the Temple of Preah Vihear is situated in territory under the sovereignty of the Kingdom of Cambodia; (4) To adjudge and declare that the Kingdom of Thailand is under an obligation to withdraw the detachments of armed forces it has stationed, since 1954, in Cambodian territory, in the ruins of the temple of Preah Vihear; (5) To adjudge and declare that the sculptures, stelae, fragments of monuments, sandstone model and ancient pottery which have been removed from the temple by the Thai authorities since 1954 are to be returned to the government of the Kingdom of Cambodia by the government of Thailand.
In July 2011, ICJ issued a provisional measures by ordering (1) both Parties shall immediately withdraw their military personnel currently present in the provisional demilitarized zone, as defined in paragraph 62 of the present Order, and refrain from any military presence within that zone and from any armed activity directed at that zone; (2) Thailand shall not obstruct Cambodia’s free access to the Temple of Preah Vihear or Cambodia’s provision of fresh supplies to its non-military personnel in the Temple; (3) Both Parties shall continue the co-operation which they have entered into within ASEAN and, in particular, allow the observers appointed by that organization to have access to the provisional demilitarized zone; (4) Both Parties shall refrain from any action which might aggravate or extend the dispute before the Court or make it more difficult to resolve.
After the public hearings taking place on 15-19 April 2011, the court delivered its judgement on 11 November 2013. In its Judgment on Cambodia’s request for interpretation, the Court (1) Finds, unanimously, that it has jurisdiction under Article 60 of the Statute to entertain the Request for interpretation of the 1962 Judgment presented by Cambodia, and that this Request is admissible; (2) Declares, unanimously, by way of interpretation, that the Judgment of 15 June 1962 decided that Cambodia had sovereignty over the whole territory of the promontory of Preah Vihear, as defined in paragraph 98 of the present Judgment, and that, in consequence, Thailand was under an obligation to withdraw from that territory the Thai military or police forces, or other guards or keepers, that were stationed there.
Both Thai and Cambodian sides are satisfied with the court’s judgement. It is regarded as a win-win for both countries and peoples and a means to end the prolonged border dispute between the two countries. The potential tensions between the two countries after the court’s verdict have been easing although the opposition and nationalist groups in Thailand are protesting against the verdict. However, both countries need to work together to implement the court’s judgement especially with regard to the demarcation of the promontory of the Preah Vihear temple. In Paragraph 98 the court provides indications concerning how to measure that promontory area as follows: “It appears that the limits of the promontory of Preah Vihear, to the south of the Annex I map line, consists of natural features. To the east, south and south-west, the promontory drops in a steep escarpment to the Cambodian plain. The parties were in agreement in 1962 that this escarpment, and the land at its foot, were under Cambodian sovereignty in any event. To the west and north-west, the land drops in a slope, less steep than the escarpment but nonetheless pronounced, into the valley which separates Preah Vihear from the neighbouring hill of Phnom Trap, a valley which itself drops away in the south to the Cambodian plain. The Court left Phnom Trap from the judgement. The Court considers that Phnom Trap locates outside the disputed area and the 1962 Judgment did not address the question whether it was located in Thai or Cambodian territory.