Pakistan closed its air space for Indian airlines and rejected New Delhi's suspension of a critical water sharing treaty in retaliation for India's response to a militant attack on tourists in Jammu and Kashmir.
The latest diplomatic crisis was triggered by the killing of 26 men at a popular tourist destination in India's Jammu and Kashmir territory on Tuesday, in the worst attack on civilians in India since the 2008 Mumbai shootings.
New Delhi said there were cross-border elements to the attack and downgraded ties with Pakistan on Wednesday, suspending a 1960 treaty on sharing waters of the Indus River and closing the only land crossing between the neighbours.
On Thursday, Pakistan said it was closing its air space to Indian-owned or operated airlines, suspending all trade including through third countries and halting special South Asian visas issued to Indian nationals.
Islamabad will also exercise the right to hold all bilateral accords with India, including the 1972 Simla Agreement, in abeyance, Pakistan's Prime Minister's office said in a statement.
The Simla Agreement was signed after the third war between the two countries and lays down principles meant to govern bilateral relations, including respect for a ceasefire line in Kashmir.
The Indus Waters Treaty, mediated by the World Bank, split the Indus River and its tributaries between the neighbours and regulated the sharing of water. It had so far withstood even wars between the two sides.
Pakistan's response came hours after Indian Prime Minister Narendra Modi vowed to pursue, track and punish the militants who separated the men among the tourists in Kashmir's Pahalgam area and shot them dead.
It also came after the Indian foreign ministry announced the suspension of all visa services to Pakistanis and revoked visas that have already been issued.
Modi has called an all-party meeting with opposition parties on Thursday to brief them on the government's response to the attack.

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