Pakistan has warned it could suspend a critical peace treaty with India in the wake of recent violence in the disputed province of Kashmir, with tensions between the two nations continuing to escalate.
Pakistan said it may suspend the Simla Agreement between the two nations, which is a significant peace treaty signed after the 1971 India-Pakistan war in which Pakistan and India agreed to settle future differences through peaceful bilateral negotiations, without third-party intervention or violence.
Under the agreement, India and Pakistan went on to establish the Line of Control, previously called the Ceasefire Line, a highly militarised de facto border that divides disputed Kashmir between the countries.
Pakistan's warning to India comes in the wake of a diplomatic offensive from New Delhi against Islamabad, blaming it for a deadly attack that killed 26 people, mostly tourists, in disputed Kashmir.
India accused Pakistan of supporting "cross-border terrorism" on Wednesday night and imposed diplomatic measures, including downgrading diplomatic ties, suspending a key water-sharing treaty and closing the main land border crossing with Pakistan.
Pakistan has denied the accusations from India, and a previously unknown militant group calling itself Kashmir Resistance has claimed responsibility for the attack.
In a statement issued on Thursday, India's foreign ministry said all visas issued to Pakistani nationals will be revoked with effect from Sunday. It also advised Indian citizens not to travel to Pakistan.
In retaliation, Pakistan cancelled visas for Indian nationals, closed its airspace for all Indian-owned or Indian-operated airlines, and suspended all trade with India, including to and from any third country.
Diplomatic ties between the two countries were already weak, particularly after India revoked Kashmir's semiautonomous status in 2019.
India and Pakistan each administer a part of Kashmir, but both claim the territory in its entirety.
The two sides have long accused each other of backing forces to destabilise one another, and New Delhi describes all militancy in Kashmir as Pakistan-backed terrorism.
Pakistan denies this, and many Muslim Kashmiris consider the militants to be part of a home-grown freedom struggle.
India said a number of Pakistani diplomats were asked to leave New Delhi and Indian diplomats were recalled from Pakistan.
Diplomatic missions in both countries will reduce their staff from 55 to 30 as of May 1, India's foreign secretary, Vikram Misri, announced Wednesday night.
Mr Misri also said the only functional land border crossing between the countries would be closed, adding that India was also suspending a landmark water-sharing treaty.
The Indus Water Treaty, brokered by the World Bank in 1960, allows for sharing the waters of a river system that is a lifeline for both countries, particularly for Pakistan's agriculture.
The treaty has survived two wars between the countries, in 1965 and 1971, and a major border skirmish in 1999.
On Thursday, Prime Minister Narendra Modi called for an all-party meeting with opposition parties to brief them on the government's response to the attack.
Some fear New Delhi may move beyond diplomatic sanctions as the country's media and leaders from Mr Modi's Hindu nationalist ruling party call for military action.
Praveen Donthi, senior analyst with the International Crisis Group, said framing the Kashmir conflict as a security crisis of Pakistan's creation, "which can be resolved only through harsh talk and actions", brings political dividends to Mr Modi's government but could also leave it with few options in times of crises.
"The immense public pressure on the Modi government to retaliate strongly and militarily is self-created," said Mr Donthi.
"Soon, there will be no options left unless New Delhi starts looking to address the roots of political unrest in Kashmir," Mr Donthi said.
In 2019, when insurgents rammed a car packed with explosives into a paramilitary convoy, killing 40 soldiers, India claimed to strike a militant training camp inside Pakistan.
Pakistan responded with air raids, downed an Indian military aircraft and captured an Indian pilot who was later released.
Two years later, in 2021, the two countries renewed a previous ceasefire agreement along their border, which has largely held despite attacks on Indian forces by insurgents in Kashmir.
The attack shocked residents of Kashmir, where militants fighting against Indian rule have rarely targeted tourists and have mainly mounted their attacks against Indian forces.
In Kashmir, locals shut down markets, businesses and schools on Wednesday in protest, amidst worries that the attack would hurt the region's tourism economy.
Funerals of several of those killed were also held across some Indian cities, and people participated in candle-lit vigils at some places, including in Srinagar, the main city in Kashmir.
