India’s unilateral suspension of the Indus Water Treaty (IWT) in April 2025, following the Pahalgam terror attack,marks a significant challenge to International treaty law and regional stability. The IWT, brokered by the World Bank has long served as a rare example of sustained cooperation between India and Pakistan by allocating the western rivers to Pakistan and the eastern ones to India. By invoking Articles 60 and 62, of the Vienna Convention on the Law of Treaties (VCLT), India claims justification for its actions on the grounds of a “material breach” and “a fundamental change of circumstances.” These narrow exceptions to the principle of pacta sunt servanda (treaties must be kept) are subject to strict thresholds under International Law. A close examination of these provisions, their thresholds and relevant international jurisprudence reveals that India’s legal rationale is deeply flawed.
Article 60 VCLT- Material Breach of a Treaty
Article 60 allows termination or suspension of a treaty only if the other party commits a material breach. A material breach is defined as either repudiation of the treaty or violation of a provision essential to achieving the treaty’s object or purpose.
Bruno Simma, a former judge of the ICJ and an eminent authority on International law has argued that the Article does not refer to the intensity or gravity of the breach and instead focuses on the “character of the treaty obligation” that is being breached. The Gabcíkovo-Nagymaros Project (Hungary/Slovakia, 1997) decision regardingthe “Treaty Concerning the Construction and Operation of the Gabcikovo-Nagymaros System of Locks (Treaty).” This treaty was initially signed between Hungary and Czechoslovakia to construct a joint hydroelectric dam, improve navigation and protect against flooding of the banks on the Danube River. Hungary abandoned work on the Nagymaros project, citing environmental concerns, and later notified Czechoslovakia of its intention to terminate the 1977 Treaty. Czechoslovakia responded by unilaterally diverting the Danube and operating the Gabčíkovo system for its own benefit.
The International Court of Justice (ICJ) rejected Hungary’s attempts to invoke Article 60 based on arguments that Czechoslovakia (now Slovakia) violated Articles 15, 19 and 20 of the treaty as well as general principles of International Law. It firstly held that Article 60 could only be invoked by specific treaty breaches, hence breach of International Law or other treaties was not a ground. Secondly, Articles 15, 19 and 20 mentioned the Joint Action Plan which could not be unilaterally breached. Here, Hungary itself contributed to the deadlock by suspending works at Nagymaros. Furthermore, Czechoslovakia’s construction of the diversion (Cunovo Dam) was legal before the time it diverted the water of the Danube. Hence Hungary’s termination based on the construction itself was premature.
In light of this, India’s claim that Pakistan’s alleged support for cross-border terrorism constitutes a material breach is legally unsustainable. India’s argument relies on extraneous conduct — terrorism — which, however grave, does not relate to the treaty’s water-sharing provisions. The IWT is a technical water-sharing agreement, and Pakistan’s compliance with its water allocation and technical cooperation obligations is not in dispute. No clause in the IWT makes peace or non-support for militancy an “essential condition” for its operation. Furthermore, the IWT was negotiated in the backdrop of the 1971 war between India and Pakistan and it was intended to endure such conflicts. In light of such a purpose, the present suspension by India seems arbitrary. Similarly Judge Oda’s dissent highlighted that the Treaty accounted for the environmental impact at the time of its entering into force.
Even if Pakistan’s alleged actions were framed as broader violations of International obligations, Article 60(5) VCLT limits the right to suspend treaties where provisions protect the human person. While the IWT is not a humanitarian treaty per se, its function – ensuring access to water for millions – implicates fundamental rights to life and livelihood. Unilaterally cutting off river flows, even as retaliation, risks breaching these norms. Under both the VCLT and ICJ jurisprudence, India cannot lawfully invoke Article 60 on these grounds alone.
Article 62 VCLT- Fundamental Change of Circumstances (Rebus Sic Stantibus)
Article 62, VCLT codifies the doctrine of rebus sic stantibus, allowing a state to withdraw from or terminate a treaty only if a truly fundamental and unforeseeable change in circumstances has occurred. The provision is intentionally restrictive: the change must have been unforeseen at the time of the treaty’s conclusion, must have constituted an essential basis of the parties’ consent, and must radically transform the extent of obligations still to be performed.
Mark E Villiiger, a Swiss judge who served in the European Court of Human Rights for Liechtenstein also emphasises the narrow interpretation of the Article by stating that even if a change is fundamental, the Article may not be used as a ground for termination unless exceptionally strict conditions, which are to be applied cumulatively have been met. The ICJ has consistently interpreted Article 62 narrowly. In Fisheries Jurisdiction (UK v. Iceland, 1973), the ICJ rejected Iceland’s attempt to terminate a fisheries agreement, holding that changes in fishing conditions and legal regimes, while significant, were neither entirely unforeseen nor sufficient to overturn the “essential basis” of the treaty’s consent. In other words, the increasing burden of the performance of the obligations is not seen and instead it must be shown that the change of circumstances had rendered the performance “essentially different from what was earlier undertaken.” Similarly, in Gabcíkovo-Nagymaros the ICJ acknowledged Czechoslovakia’s breakup as a political change but ruled it did not constitute a fundamental change under Article 62 as the treaty’s core purpose remained achievable. The application of Article 62 only in exceptional cases being a foundational requirement has been affirmed by the International Law Commission (ILC).
To further illustrate the strict application of Article 62 VCLT, two leading cases stand out. ṁ1998, the European Court of Justice upheld the suspension of a trade agreement between the European Community and Yugoslavia only after the outbreak of war and the collapse of Yugoslav state institutions. The Court found that the maintenance of peace and functioning institutions was an essential basis for the treaty, and their unforeseen destruction radically transformed the obligations, thus justifying suspension under Article 62. Similarly, in the Netherlands–Suriname, 1982, Netherlands suspended its development assistance treaty with Suriname following a military coup and grave human rights abuses. The Dutch government argued that the coup constituted a fundamental, unforeseen change that destroyed the democratic foundation essential to the treaty’s operation, meeting Article 62’s high threshold. In both cases, the change was unforeseeable and struck at the heart of the treaties’ purposes, radically altering the obligations of the parties.
Neither demographic changes nor security concerns were considered an essential basis of consent when the IWT was negotiated. The treaty’s preamble and negotiating history show the parties’ primary objective was satisfactory utilization of the Indus Basin water through clear technical rules for allocation. The focus was on water management, mutual benefit, and dispute resolution, not on the political or demographic context, which was already volatile at the time.
Unlike the situations in Racke and the Netherlands–Suriname case, India’s invocation of Article 62 to justify suspension of the IWT is fundamentally flawed. The demographic changes, increased water demand, and persistent security concerns cited by India are evolutionary and foreseeable developments. The IWT was designed to withstand precisely such volatility, and its core obligations remain unchanged. Thus, the grounds raised for India’s reliance on Article 62 fall short –
A. Foreseeability: Population growth, rising water demand, and regional security volatility were all foreseeable at the time the IWT was negotiated.
B. Essential Basis: The IWT’s core purpose is technical water allocation and management, not the political or demographic context.
C. Radical Transformation: The obligations under the IWT—allocation and management of river flows—remain fundamentally unchanged. India’s desire to use more water or address security concerns does not amount to a radical transformation of the treaty’s core commitments.
ICJ and arbitral tribunals have emphasized that only changes that destroy or fundamentally alter the factual circumstances underpinning the treaty, such as the drying up of a river or a catastrophic natural event, might qualify under Article 62. Even then, Article 62(2) precludes reliance on this doctrine if the change is attributable to the party seeking to invoke it.
The IWT’s design precludes Unilateral Exit
Article XII of the IWT explicitly states that the treaty can only be modified or terminated by mutual agreement between the parties, thus, deeming unilateral withdrawal or suspension impermissible. The underlying agenda was to ensure permanence and stability and insulate the treaty from political fluctuations. The ILC’s Second Report on the Law of Treaties, which laid the groundwork for the VCLT emphasised that explicit provisions, if mentioned, in the Treaty for its termination or suspension, override the general doctrine of fundamental change of circumstances. Article 60(4), VCLT also gives precedence to treaty-specific procedures on breach, reinforcing the IWT’s bar on unilateral exit.
Instead of adhering to the IWT’s internal dispute-resolution procedures – approaching the Permanent Indus Commission, requesting a Neutral Expert, or seeking arbitration – India simply unilaterally suspended the IWT and declared the Court of Arbitration “illegal and void.” This directly contravenes the foundational structure and procedural safeguards embedded in both the IWT and the VCLT. Article 65, VCLT requires adherence to a formal process for any suspension or termination (notifying the other party and a waiting period), which was also not observed herein. Such actions undermine the principle of good faith in treaty performance (VCLT Article 26) and risk setting a precedent for the politicization of essential resources.
Comparative Practice Undermines India’s claim
India’s attempt to suspend the IWT by invoking Articles 60 and 62 of the VCLT is extremely rare in international water law. Although upstream states like Turkey, Ethiopia, and China have exercised unilateral control over transboundary rivers, none have successfully invoked VCLT provisions to justify their actions. This underscores the legal fragility of unilateral actions in transboundary water contexts. Turkey reduced Euphrates flows to Syria and Iraq citing security and development needs but avoided invoking treaty law, as no binding agreement governed water allocations. Ethiopia’s unilateral filling of the Grand Ethiopian Renaissance Dam (GERD) was framed around sovereignty and historical injustice rather than a formal Article 62 argument. Similarly, China has withheld hydrological data and altered flows on the Mekong and Brahmaputra but remains outside most treaty frameworks, sidestepping legal scrutiny. Notably, none of these states have been vindicated by international courts, and where legal justifications were attempted, such as in Hungary’s failed Article 60 defense in Gabcíkovo-Nagymaros, they were rejected. India’s case is distinct in that it is party to a long-standing, binding treaty, making its legal obligations clearer and more enforceable. By unilaterally suspending the IWT, India risks violating not only treaty law but also customary international principles like equitable utilization and the no-harm rule, as enshrined in the UN Watercourses Convention.
Conclusion
The IWT remains legally binding, and India’s suspension constitutes a breach of its international obligations. It undermines the good faith performance of treaties (VCLT Article 26) and suggests in the words of one analysis, a “weaponisation of water” Upholding pacta sunt servanda is essential not only for legal coherence, but also for the millions who depend on the Indus.
Shambhavi Singh is a practicing lawyer in the Supreme Court and the Delhi High Court, and Rudra Singh Krishna is a fourth-year law student at WBNUJS.
Picture Credit: PTI