India moved on Friday to formally suspend its participation in the 1960 Indus Waters Treaty with Pakistan, government officials announced in New Delhi, marking one of the most significant diplomatic escalations between the nuclear-armed neighbours in decades. The decision follows the deadly Pahalgam terror attack in Kashmir that killed dozens of tourists last week and has driven a rapid deterioration in bilateral relations.

External Affairs Ministry spokesperson Randhir Jaiswal confirmed that India had issued formal notice to Islamabad, citing Pakistan's alleged support for cross-border terrorism as incompatible with continued cooperation under the World Bank-brokered treaty, which governs the sharing of six rivers across the Indus basin. The treaty has survived two full-scale wars and multiple crises since its signing under Prime Ministers Nehru and Ayub Khan.

The Indian government has already taken a series of punitive steps this week, including expelling Pakistani diplomats, suspending visas, and closing the Attari-Wagah land crossing. The appointment of special public prosecutor Karambir Singh Nalwa to lead the Pahalgam attack trial, announced Wednesday, signals New Delhi's intent to pursue legal accountability alongside diplomatic pressure.

Pakistan's Foreign Ministry issued a statement calling the suspension 'illegal under international law' and warning of 'serious consequences for the region's water security.' Islamabad has placed its own armed forces on elevated alert and requested an emergency session of the United Nations Security Council to discuss what it characterised as Indian aggression.

Water experts and international observers warned that suspension of the treaty could trigger a humanitarian and agricultural crisis in Pakistan's Punjab province, which depends heavily on Indus system rivers. The World Bank, which serves as the treaty's guarantor, said it was 'deeply concerned' and called on both parties to return to diplomatic channels. The situation is being monitored closely by the United States and China, both of which have significant strategic interests in the stability of the subcontinent.