Pakistan on Sunday expressed “utmost satisfaction” over a supplemental award by the Permanent Court of Arbitration (PCA), maintaining it affirmed Islamabad’s position on the Indus Waters Treaty placing “substantive limits on India’s water-control capability” on the river system’s western rivers.
The decision, pertaining to maximum pondage or the maximum volume of water that can be stored in a reservoir, arises from design disputes concerning the Ratle Hydroelectric Plant and the Kishenganga Hydroelectric Project in India-held Kashmir.
In an official statement, Pakistan noted the supplemental award was issued on May 15. It recalled that Pakistan had initiated arbitration proceedings regarding the Indus Waters Treaty against India in 2016, adding that even though Delhi continues to boycott the proceedings, the court shares its procedural updates and decisions with both Indian and Pakistani Indus water commissioners ex-officio.
The latest supplemental award, read the statement, affirmed Islamabad’s “central position that the treaty places substantive limits on India’s water-control capability on the western rivers.” It stressed that such limits were not mere formalities and applied at the planning and design stage. These limits, it said, cannot be satisfied merely by a later assurance of operational restraint.
“Pondage for a run-of-river Plant must be justified by real project needs, actual expected operation, site hydrology, hydraulic conditions, power-system requirements, and the information and explanation required under the treaty,” read the statement. It stressed that building on the PCA’s Award on Issues of General Interpretation of the IWT on Aug. 8, 2025, the supplemental award gave practical effect to the standard that installed capacity and anticipated load must be realistic, well-founded and defensible.
“Installed capacity must correspond to actual expected operation, hydrologic and hydraulic data, and treaty requirements. Anticipated load must correspond to actual expected operation and to the projected needs of the power system the plant is intended to serve,” it said.
“India cannot justify increased pondage through imagined capacity, artificial load curves, unrealistic peaking assumptions, or bare assertions of compliance with paragraph 15 release limits,” it said. “Paragraph 15 remains an operational constraint, but it is not a substitute for an evidence-based justification of the water-control capacity sought. Any different operating pattern must be supported by specific information and underlying data produced by India,” it added, referring to the paragraph that elaborates on “interference with the waters” under the pact.
The statement said the award had strengthened Pakistan’s review rights. “India must provide Pakistan with sufficient information and explanation to assess treaty compliance. If India fails to do so, it fails to carry its burden of establishing that the proposed maximum pondage satisfies Paragraph 8(c) of Annexure D,” it maintained.
The government statement said the PCA had also confirmed that “any applicable minimum-flow obligation must be taken into account in calculating pondage required for firm power where such obligation exists and is not otherwise satisfied. Paragraph 15 release requirements do not automatically satisfy such an obligation.” It said Pakistan “also notes the Court’s earlier holding that the awards of a court of arbitration are final and binding on the parties and have otherwise controlling legal effect for subsequent treaty bodies on relevant questions of treaty interpretation.”
The government said Islamabad would place these interpretations before the neutral expert process, consistent with treaty procedures and applicable confidentiality arrangements. It emphasized that Pakistan remains committed to the Indus Waters Treaty, its dispute-resolution procedures, and the peaceful settlement of water-related differences.
“Pakistan will continue to protect its rights under the IWT and will pursue every lawful and diplomatic means to ensure that hydroelectric projects on the western rivers are designed and operated strictly within treaty limits,” it said. “The award is a strategic consolidation of Pakistan’s treaty position: maximum pondage must be realistic, evidence-based, hydrologically grounded, power-system justified, treaty-compliant, and incapable of inflation through artificial assumptions,” it added.
India’s response
Separately, the Indian foreign ministry has issued a statement rejecting the PCA’s decision. “The illegally constituted so-called Court of Arbitration has, on May 15, 2026, issued what it termed an award concerning maximum pondage supplemental to the award on issues of general interpretation of the Indus Waters Treaty,” it said.
“India categorically rejects the present so-called award, just as it has firmly rejected all prior pronouncements of the illegally constituted [Court of Arbitration],” it said, adding Delhi “never recognized the establishment of this so-called [Court]. Any proceeding, award, or decision issued by it is null and void.”
The statement stressed that India’s decision to unilaterally hold the Indus Waters Treaty in abeyance remained in force.
The IWT was brokered by the World Bank in 1960, allocating water of three western rivers—Indus, Jhelum and Chenab—to Pakistan, and the water of three eastern rivers—Ravi, Beas and Sutlej—to India. The Treaty is presently under threat, as India in April 2025 announced a unilateral suspension of its obligations after the Pahalgam attack. Delhi blamed the attack on Islamabad though has yet to offer any evidence to support such allegations.