By Tani Thilakaratne
India and Sri Lanka share an intricate bilateral partnership and a legacy of over 2500 years of intellectual, cultural, and religious interactions. Over time, both countries have recognized the value of this relationship in fostering peace and stability, particularly as the Indo-Pacific region emerges as a region of strategic significance in global geopolitics.
Since Sri Lanka’s independence in 1948, these relations have progressed from a postcolonial partnership into a multidimensional partnership shaped by shifting regional power dynamics.
To embark on a new chapter in Indo-Sri Lanka relations, seven Memoranda of Understanding were signed in 2025. One of the most significant among them is the defense agreement that embodies the commitment of both governments to enhance regional security, maritime cooperation, and mutual trust. Simultaneously, it reflects India’s and Sri Lanka’s dedication to support a balanced multipolar regional order.
Historical Background: Indo-Sri Lanka Relations
Post-independence, the relationship flourished through the Sirimavo-Shastri Pact in 1964. However, during Sri Lanka’s civil war in 1987, India’s deployment of the Indian Peace Keeping Force (IPKF) altered the bilateral dynamics, causing mistrust. Relations were further strained in 1991, with the assassination of the former Indian Prime Minister Rajiv Gandhi by the Liberation Tigers of Tamil Eelam (LTTE). Following the military defeat of the LTTE, there was a gradual reconciliation through India’s assistance to Sri Lanka in reconstruction activities, diplomatic cooperation between the two countries on important global issues, and collaboration in peace keeping initiatives.
India and Sri Lanka are members of various regional groupings. Although SAARC has been inactive for the last several years, the two countries are active partners in BIMSTEC. Cooperation in regional affairs continues to define contemporary Indo-Sri Lanka relations. Sri Lanka’s geographical positioning remains crucial to India’s trade routes and maritime security interests. However, there is concern about Sri Lanka’s potential vulnerability to debt-trap diplomacy and China’s presence in the country through the Belt and Road Initiative. Nonetheless, to emphasize inclusive regional development, India has articulated the “Neighborhood First” policy and “Security and Growth for All in the Region”, conveying to Sri Lanka the need to pursue a delicate strategic balance between China and India.
The 2025 Defense Agreement
While not publicly disclosed, analysts define this MoU as an expanded framework aimed at improving and institutionalizing bilateral defense cooperation for 5 years. Both countries have the right to terminate the MoU, by giving three months of advance written notice. According to India’s Foreign Secretary, this agreement “will make existing defense cooperation initiatives more structured.” The agreement institutionalizes joint maritime surveillance and patrols in the Indian Ocean to raise awareness against piracy, illegal migration, unregulated fishing, illegal armed robberies, and drug trafficking.
The MoU emphasizes cooperation in the “areas of science and defense technology, research and development”, allowing Sri Lanka access to Indian-manufacturing platforms, coastal surveillance, and communication infrastructure. Additionally, it highlights training defense personnel through peacekeeping training and programs regarding Humanitarian Assistance and Disaster Relief (HADR), ensuring preparedness for any future natural disasters and public health emergencies. Beyond training, the agreement facilitates direct cooperation in the defense industry and exchange programs between military forces. Significantly, the primary objective in this MoU is to enhance interoperability, capacity building, and trust between the armed forces of both nations.
Implications
Foreign policy analyst Mr. Abeygoonasekara mentions that this agreement aligns with India’s ambitions to place itself as a “net security provider” in the IOR.
For India, this MoU addresses emerging regional threats, such as managing China’s growing presence in the Indian Ocean region. Instances such as the docking of Chinese submarines in Colombo and Chinese research ships operating near Indian waters can now be handled through better understanding and in a coordinated manner. India’s maritime domain awareness can be expanded through projects like the National Maritime Domain Awareness Centre and Information Fusion Centre in collaboration with Sri Lanka.
For Sri Lanka, the agreement facilitates access to capacity-building initiatives, advanced defense training and technology, and maritime surveillance support. Its geographical location can be leveraged to attract investments and maritime trade opportunities while navigating shared security goals in the IOR. Regionally, this partnership presents a broader diplomatic message on South Asian solidarity and indigenous alternatives for South Asian Security. Moreover, it encourages stability in maritime governance frameworks and responses to non-security challenges.
However, concerns may arise from China, mentioning that this agreement is a part of the containment strategy for limiting their economic interests in Sri Lanka.
Challenges ahead
To mitigate external perceptions (such as Chinese suspicions of a containment strategy), it is essential to maintain transparency regarding the agreement’s scope and limitations. Sri Lanka must delicately balance its foreign policy between China and India to gain benefits from both without isolating either.
During implementation, challenges may arise regarding budgetary coordination and sustaining political will in both countries. Questions may arise regarding the financial viability of defense cooperation due to economic constraints.
The 2025 Indo-Sri Lanka defense agreement represents a strategic partnership in addressing modern security challenges. It has the potential to address shared threats from external powers, redefine South Asian maritime security, and institutionalize regional partnerships. The agreement embodies the interconnected security interests of both countries, and that cooperative commitment will provide practical outcomes. The success of this partnership will depend upon transparent implementation, gradual expansion of emerging security domains, and clear political commitment. If implemented effectively, this agreement may contribute to a peaceful and resilient Indian Ocean region in the decades to come.
Tani Thilakaratne is a postgraduate in International Relations, Leiden University. The views expressed in the above piece are personal and solely those of the author. They do not necessarily reflect the views of Kalinga Institute of Indo-Pacific Studies.
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