Why is it in News?
- December 2025 escalation:
- Thailand launched airstrikes inside Cambodia after renewed border clashes.
- Both sides accused each other of violating a U.S.-brokered ceasefire (Oct 2025).
- U.S. intervention:
- After calls with both leaders, President Donald Trump announced a ceasefire on December 12.
- Marks the worst flare-up since July 2025 fighting, which killed dozens and displaced over 3 lakh civilians.
Relevance
GS II:
- International relations: border disputes, ICJ rulings, ASEAN role.
- Role of external powers (U.S. mediation).
GS III:
- Internal security (regional instability spillovers).
Basics: Thailand–Cambodia Border
- Length: ~817 km.
- Nature: Partially demarcated, heavily forested, mountainous.
- Dispute origin: Colonial-era boundary treaties (1904 & 1907).
- Strategic-cultural sensitivity:
- Hosts ancient Khmer temples, especially Preah Vihear.

What is the Border Dispute About?
- Core issue:
- Sovereignty over un-demarcated stretches of the border.
- Colonial legacy:
- Treaties between France (Cambodia) and Siam (Thailand).
- Boundary supposed to follow Dangrek Mountains watershed.
- French maps placed key temples on the Cambodian side.
- Result:
- Thailand disputes map validity; Cambodia relies on them for claims.
Centrality of Preah Vihear Temple
- Temple:
- 11th-century Hindu temple (Shaivite), symbol of Khmer civilisation.
- History: Construction began in the 9th century, with major expansions in the 11th and 12th centuries under Khmer kings Suryavarman I and Suryavarman II.
- Architecture: Unlike most Khmer temples, which face east, Preah Vihear follows a linear north-south axis over an 800-meter length, with a series of sanctuaries, pavements, and staircases. It is known for its exceptional stone carvings.
- ICJ rulings:
- 1962: Temple belongs to Cambodia.
- 2013 clarification: Cambodia has sovereignty over most surrounding area.
- Continuing friction:
- Thailand accepts temple ruling but disputes adjacent land.
- Nationalism factor:
- Cambodia: Cultural heritage & post-colonial sovereignty.
- Thailand: Territorial integrity & resistance to perceived loss.


