India and Pakistan have taken significant steps to cut diplomatic, trade, and travel ties following a deadly attack in Pahalgam, one of the most popular tourist destinations in Indian-administered Kashmir on Tuesday, which resulted in the deaths of 26 people, most of them Indian tourists.

According to reports, India cancelled all visas for Pakistani nationals, effective Sunday. Pakistanis already in India must leave before their visas expire. 

India also closed the Wagah land border, reduced diplomatic staff in Islamabad, and suspended its participation in the Indus Waters Treaty. The treaty, signed in 1960, governs water sharing of six rivers between the two countries. It has never been suspended before.

India’s response comes after it accused Pakistan of being responsible for Tuesday’s attack, particularly citing Pakistan’s support for terrorist groups in the region. 

The attack in Pahalgam was claimed by The Resistance Front (TRF). Indian authorities have previously stated that TRF is an offshoot of Lashkar-e-Taiba, a Pakistan-based militant group that is widely believed to be supported by elements within the Pakistani state. 

Pakistan has denied any involvement in the attack. “India has time and again played the blame game and if there is proof of Pakistan’s involvement [in Pahalgam], please share it with us and the world,” Pakistani Foreign Minister Ishaq Dar said.

In response to India’s actions, Pakistan closed its airspace to Indian-owned or operated airlines. It also suspended all trade with India, including trade through third countries.

The Pakistani government also warned that any disruption of water under the treaty would be considered an “act of war.”