India's Foreign Ministry on Wednesday said it would suspend a key water-sharing treaty with Pakistan and close a key border crossing as part of a suite of diplomatic measures against its neighbor.
New Delhi said Islamabad needed to end "cross-border terrorism" after an attack in the Kashmir region that killed 26 civilians.
There was international condemnation after gunmen opened fire on tourists near the picturesque town of Pahalgam in Indian-administered Kashmir in the region's worst terror attack on civilians in decades.
How is India responding to the Kashmir attack?
Foreign Secretary Vikram Misri said "cross-border linkages" to the terrorist attack had been revealed in a security cabinet meeting, before citing a raft of measures that India would be taking against Pakistan.
The secretary said the Indus Water Treaty would be halted with immediate effect.
"The Indus Waters Treaty of 1960 will be held in abeyance with immediate effect, until Pakistan credibly and irrevocably abjures its support for cross-border terrorism", Misri told reporters.
Pakistan is heavily dependent on the water from the Indus River and its tributaries for agriculture and drinking water. The treaty's suspension could mean Pakistan faces severe water shortages.
Misri also said India would close the main land border, at Attari-Wagah, "with immediate effect."
Pakistan relies heavily on the Attari-Wagah crossing for trade and is more dependent on it than India.
Meanwhile, he said, Pakistani nationals would not be allowed to travel to India under a regional visa exemption scheme — and that Pakistani nationals in India traveling as part of it had 48 hours to leave the country.
Misri said there would be diplomatic consequences with defense advisors to the Pakistani High Commission in New Delhi being declared persona non grata and having a week to leave India. India would be withdrawing its advisors from the Indian High Commission in Islamabad, he added.
Pakistan's Foreign Minister Ishaq Dar announced that Prime Minister Shehbaz Sharif would hold a meeting of the National Security Committee on Thursday to respond to India's statement.
The committee of senior civil and military officials is summoned in cases of external threat or major terror attack.
Indian PM returns home early
Indian Prime Minister Narendra Modi had cut short his trip to Saudi Arabia and returned to New Delhi on Wednesday following the attack for a meeting of the cabinet security council.
Security in the region has been beefed up since Tuesday's attack, which targeted civilians, resulting in the death of at least 26 people, with another 17 injured, in what appears to be the worst civilian attack in years.
A spokesperson for the Pakistani Foreign Ministry said his country was concerned about the loss of lives in the region, adding it wished the injured a speedy recovery.
Nevertheless, the violence has raised the threat of increased tensions between India and Pakistan, with many fingers pointed at Pakistan for the ongoing conflict in Kashmir.
Tuesday's attack drew widespread condemnation and came at a time when US Vice President JD Vance was visiting India on a four-day trip.
US President Donald Trump and EU Commission President Ursula von der Leyen
were among the leaders who expressed support to the Indian people.
The violence was one of the deadliest episodes in a long history of conflict in the disputed region that is divided principally between India and Pakistan.
Promise to trace perpetrators and plotters
Modi was briefed by National Security Adviser Ajit Doval and Foreign Minister S. Jaishankar upon his arrival at the airport, according to local reports.
Indian Finance Minister Nirmala Sitharaman, part of the body responsible for domestic affairs, also cut short her trip to the US and Peru.
Interior Minister Amit Shah met with family members of those who were killed and injured in the attack in the nearby city of Srinagar.
Meanwhile, India's Defense Minister Rajnath Singh vowed to "not only trace those who perpetrated the attack but also trace those who conspired to commit this nefarious act on our soil."
Tens of thousands of security forces were deployed to patrol the region and set up additional checkpoints, as former militants were brought in for questioning.
The Resistance Front (TRF), an affiliate of the banned terror group Lashkar-e-Taiba (LeT), claimed responsibility for the attack on social media, according to local reports.
The TRF group reportedly formed after the Modi government scrapped the special status that granted special privileges to the people of the former state of Jammu and Kashmir in 2019.