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 killed 26 civilians.

World leaders condemned the violence that followed after gunmen opened fire on tourists near the picturesque town of Pahalgam in Indian-administered Kashmirin the region's worst attack on civilians in years.

How is India responding to the Kashmir attack?

Foreign Minister Vikram Misri said "cross-border linkages" to the attack had been revealed in a security cabinet meeting, before citing a raft of measures that India would be taking against Pakistan.

The minister 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 mainland 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 threats or major terror attacks.

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.

Cars were searched at checkpoints, as the military and police carried out missions to locate the attackers.

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.

Pahalgam attack, one of biggest in years

The assault on civilians on Tuesday has been described as a "terror attack" by Indian officials, with the region's top elected official, Omar Abdullah, posting to social media that the assault "is much larger than anything we've seen directed at civilians in recent years."

The suspected terror attack came as a shock as the picturesque Himalayan region has been relatively safe for civilians during the decades-long conflict.

The number of domestic tourists visiting Kashmir, officially called the union territory of Jammu and Kashmir, has increased in recent years.

The last major assault in the region took place in 2019, when a suicide bomber killed 40 members of Indian security forces.

A Pakistan-based terror group Jaish-e-Mohammed (JeM) claimed responsibility for the attack and India responded by carrying out strikes in northwestern Pakistan. 

Edited by: Alex Berry