Arunachal–Assam Boundary Settlement

Arunachal–Assam Boundary Settlement

Why in News? 

In a historic milestone, Arunachal Pradesh and Assam officially installed their first joint border pillar at Seijosa on February 22, 2026. This physical demarcation follows the Namsai Declaration, which aims to resolve decades of Arunachal–Assam Boundary Dispute and ensure lasting peace. 

What is the Arunachal Pradesh–Assam Inter-State Boundary Dispute?

• About: The Arunachal Pradesh–Assam boundary dispute is a long-standing territorial conflict over administrative control of land along their 804.1-km inter-state boundary. The dispute mainly concerns forest tracts, revenue villages and tribal-inhabited frontier areas.

• Geographical Extent: The dispute extends across 8 districts of Assam and 12 districts of Arunachal Pradesh, covering large stretches of foothill plains and tribal frontier regions. It impacts more than 700 km of the shared boundary, making it one of India’s most complex inter-state territorial disagreements.

• Background: The conflict originates from the 1873 Inner Line Regulation introduced by the British to separate plains from hill tribal areas. In 1915, the region became the North-East Frontier Tracts, later renamed the North-East Frontier Agency (NEFA), administered by Assam after Independence without clearly demarcated legal borders. 

• • • In 1951, Gopinath Bordoloi Committee recommended transferring about 3,648 sq. km of plains from NEFA to Assam’s Darrang and Lakhimpur districts for administrative convenience. Arunachal Pradesh has consistently rejected this move as arbitrary and non-consultative.
    • The dispute intensified after Arunachal Pradesh became a Union Territory in 1972 and later a full-fledged state in 1987, when demands emerged to reclaim historically administered tribal land transferred earlier to Assam during boundary reorganisation. 
    • The boundary demarcation began in 1972, with 396 km completed by 1979. However, the process was suspended after numerous anomalies and disputes emerged during the survey, leaving the border definition incomplete. 

• Assam’s Claim: Assam maintains that the 1951 notification-based boundary is constitutionally valid and legally binding, asserting administrative control over lowland forest areas based on official surveys and recommendations of the 1960 High-Powered Tripartite Committee.

• Arunachal Pradesh’s Claim: Arunachal Pradesh argues that these transferred areas were customary tribal lands, historically governed by hill chiefs and clans, and that local communities were never consulted before the 1951 transfer—thereby demanding restoration based on historical rights.

Government and Judicial Efforts to Resolve the AP–Assam Border Dispute

• • Tripartite Committee Efforts (1979): To address rising tensions, a High-Powered Tripartite Committee involving the Centre, Assam, and Arunachal (then a Union Territory) was formed in 1979. By 1984, they demarcated approximately 489 km of the boundary. However, Arunachal Pradesh rejected the recommendations, citing inaccuracies in the Survey of India maps used.
  • Supreme Court Civil Suit (1989): Unable to reach a bilateral consensus, the Assam Government filed Original Suit No. 1/1989 in the Supreme Court. Assam sought a legal declaration of its boundary, while Arunachal Pradesh counter-claimed territories based on the 1873 Inner Line. The case remained largely stagnant for nearly two decades.
  • Tarun Chatterjee Commission (2006): The Supreme Court appointed a Local Boundary Commission in 2006, headed by Justice Tarun Chatterjee. The commission’s 2014 report suggested that Arunachal should receive several forest tracts and villages. However, Assam rejected these findings, leading to a continued legal deadlock in the apex court.
  • The Namsai Declaration (2022): A strategic shift occurred on July 15, 2022, when Chief Ministers Pema Khandu and Himanta Biswa Sarma signed the Namsai Declaration. The landmark Namsai Declaration reduced the total number of disputed villages from 123 to 86, and enabled amicable settlement of 71 villages. 
    • Both states agreed to confine the dispute strictly to issues raised before the 2007 Local Boundary Commission, preventing expansion of claims.
    • The declaration accepted the boundary delineated on 29 toposheets by the High-Powered Tripartite Committee as the basis for future realignment.
    • It initiated a “give-and-take” consensus mechanism, enabling amicable resolution of several villages.
  • Regional Committees and Ground Surveys: Following Namsai, 12 Regional Committees were constituted for both states. These panels conducted joint field visits and consulted local residents to verify the ground reality. This grassroots approach allowed the states to draft a mutually acceptable boundary line.
  • The 2023 Memorandum of Understanding (MoU): On April 20, 2023, a historic MoU was signed in New Delhi in the presence of Union Home Minister Amit Shah. This “full and final” agreement settled the status of all 123 villages, effectively ending the 50-year-old conflict.

• Status-Quo Protocol (2025): Recent district-level meetings in August 2025 institutionalised a Joint Verification Protocol to maintain status quo in unresolved villages, prevent encroachment and promote people-to-people trust-building. 

• Physical Demarcation at Seijosa (2026): The resolution moved from paper to the ground on February 22, 2026, with the installation of the first joint border pillar at Seijosa. This physical marking, supervised by senior officials, serves as the final technical step.