The Indus Waters Treaty spent most of its 66-year history as the rare success story of India-Pakistan relations, a water-sharing agreement that survived three wars. That changed on 23 April 2025, when India put the treaty "in abeyance" after the Pahalgam attack. It changed again, dramatically, on 31 August 2026, when a Hague-based Court of Arbitration ruled that India's abeyance decision has no legal basis and that the treaty remains fully binding. India rejected the ruling within a day. This piece walks through what actually happened, what the treaty allocates, and where the legal and strategic dispute stands right now.
What the treaty actually allocates
The Indus Waters Treaty divides six rivers of the Indus basin between the two countries. India received largely unrestricted use of the three Eastern Rivers, the Ravi, Beas and Sutlej, while Pakistan received primary rights to the three Western Rivers, the Indus, Jhelum and Chenab, with India permitted limited irrigation and unrestricted non-consumptive use, such as hydropower, on those same western rivers. In practical volume terms, Pakistan's share works out to roughly 80% of the system's total water, India's to around 20%, a split that has made the Western Rivers the backbone of Pakistan's irrigated agriculture ever since.
Approximate share of total Indus basin system flow allocated to each country under the treaty's river division.
The abeyance: what India did, and why
Following the 22 April 2025 attack in Pahalgam, Indian-administered Kashmir, which killed 26 people, India's government announced that the treaty would be held "in abeyance with immediate effect, until Pakistan credibly and irrevocably abjures its support for cross-border terrorism." India attributed the attack to Pakistan-backed militants; Pakistan denied involvement. India has since repeated, including through statements from its External Affairs Minister, that the abeyance stays in force regardless of other developments, such as the ceasefire agreement reached between the two countries later in 2025.
Abeyance is not the same as formal withdrawal. The treaty itself, under Article XII(4), states it can only be terminated or modified by a duly ratified treaty between the two governments, not by unilateral suspension. That legal question, whether a country can hold a treaty "in abeyance" without following that process, became the central issue in the arbitration that followed.
The 31 August 2026 ruling: what the Hague court actually decided
Pakistan had initiated arbitration proceedings against India in August 2016 under Article IX of the treaty, well before the current crisis, originally over technical disputes concerning India's Kishenganga and Ratle hydroelectric projects on the Western Rivers. Once India announced the 2025 abeyance, Pakistan brought that decision itself before the same Court of Arbitration at the Permanent Court of Arbitration in The Hague. On 31 August 2026, the Court issued two rulings at once: an Award on the Status of the Indus Waters Treaty in Respect of India's Decision on Abeyance, and an Order on Pakistan's Interim Measures Application.
The Court's unanimous conclusion rejected India's position outright, finding that India's abeyance decision has no basis under the treaty and that the Indus Waters Treaty remains fully in force and binding on both parties. As part of the interim order, the Court also restricted further construction at India's Ratle hydroelectric project on the Chenab pending a separate, ongoing technical process before a Neutral Expert. Pakistan's Foreign Office called it a decisive rejection of India's position; Pakistan's Prime Minister, Shehbaz Sharif, raised the ruling the following day at the Shanghai Cooperation Organisation summit in Bishkek, describing water as the foundation of life for the region.
India's rejection, and the deeper legal dispute underneath it
India did not participate in the arbitration hearings, held at the Peace Palace from 26 to 28 April 2026, and rejected the 31 August ruling the same day it was issued. India's Ministry of External Affairs called the Court of Arbitration "illegally constituted," stated that its decisions would have no effect on India's sovereign actions, and said it had never recognised the tribunal's legal existence.
India's underlying objection predates this specific ruling. New Delhi has argued that the treaty's own Article IX(6) bars a Court of Arbitration from adjudicating the same set of technical disputes already before the separately appointed Neutral Expert, and that the World Bank's 2022 decision to run both processes at once created exactly the kind of contradictory, legally untenable situation the treaty was designed to avoid. This was not the first ruling India rejected on these grounds. In May 2026, the same Court issued an award on a narrower technical question, maximum pondage capacity for run-of-river hydropower projects, which India also dismissed as "null and void."
The parallel track still running: the Neutral Expert process
Separate from the Court of Arbitration, a Neutral Expert appointed by the World Bank continues to examine the original technical disputes over the Kishenganga and Ratle hydroelectric projects. That process is ongoing, with the Expert's current work programme projecting a final decision around 16 July 2027. Because India recognises the Neutral Expert process as legitimate while rejecting the Court of Arbitration, this track is likely to remain the more consequential one for the two hydropower projects specifically, even as the Court of Arbitration's broader ruling on the treaty's legal status stands unresolved between the two governments.
How the dispute has unfolded
Why Pakistan treats this as an existential issue
The Western Rivers the treaty allocates to Pakistan feed the irrigation system much of the country's agricultural economy depends on. An abeyance that is never formally lifted, even if legally contested, creates lasting uncertainty over data-sharing, flood warnings and future project approvals that the treaty's mechanisms were built to guarantee. That uncertainty, not any single diversion of water, is the immediate practical cost of the dispute, regardless of how the legal argument over the Court's legitimacy is eventually resolved.
Why this matters for CSS aspirants
Few current topics combine international law, foreign policy and resource governance as directly as this one. A strong answer needs to hold three separate threads at once: what the treaty legally allows, what India actually did and why it disputes the tribunal's authority to rule on it, and what practical uncertainty this creates for Pakistan regardless of which side is eventually vindicated. Treating the August 2026 ruling as a final resolution would be a mistake; it is a significant legal development in an ongoing, unresolved dispute.
Related resources on CSS Bureau
Frequently asked questions
Is the Indus Waters Treaty still in force?
Legally, according to the Court of Arbitration's 31 August 2026 ruling, yes, the treaty remains fully binding. Practically, India maintains its April 2025 abeyance decision stays in force and has rejected the Court's authority to rule on the matter at all, so the dispute remains unresolved between the two governments.
Why did India stop honouring the treaty?
India announced the treaty would be held "in abeyance" on 23 April 2025, a day after the Pahalgam attack that killed 26 people, which India attributed to Pakistan-backed militants. Pakistan denied involvement. India has maintained the abeyance decision since, independent of other developments in bilateral relations.
Why does India reject the Court of Arbitration's rulings?
India argues the Court was improperly constituted because the treaty's Article IX(6) bars a Court of Arbitration from ruling on technical disputes already before a Neutral Expert, and that running both processes simultaneously, as the World Bank did from 2022, creates a legally contradictory situation. India has not participated in the Court's hearings and has rejected every award it has issued.
What happens next?
Two tracks continue in parallel. The Neutral Expert process on the Kishenganga and Ratle hydroelectric projects, which India still recognises, has a final decision expected around July 2027. The broader legal question of the treaty's status, addressed in the Court of Arbitration's August 2026 ruling, remains disputed between the two governments with no enforcement mechanism to compel compliance.
Conclusion
The Indus Waters Treaty is under more direct pressure now than at any point in its 66-year history. A landmark Hague ruling has said, unanimously, that India's decision to hold the treaty in abeyance has no legal basis. India has rejected that ruling as illegitimate within a day of its issuance, and the practical uncertainty for Pakistan's water security continues regardless of which legal argument eventually prevails. The dispute has moved from being primarily about specific hydropower projects to a genuine test of whether international arbitration can bind a state that refuses to recognise its authority, with the outcome still very much unresolved.
Sources and verification
Facts in this article were checked directly against the Permanent Court of Arbitration's own press release and original reporting rather than secondary summaries.