New Delhi, April 23 (IANS) Asserting that it will be unrelenting in its pursuit of those who commit acts of terror, India on Wednesday said that the perpetrators of Pahalgam terror attack will be brought to justice and their sponsors "held to account" while also announcing several measures against Pakistan which continues to sponsor terror in the Kashmir Valley.

Addressing the media after Prime Minister Narendra Modi chaired the Cabinet Committee on Security (CCS) meeting which lasted for over two hours, Foreign Secretary Vikram Misri also announced several measures "recognising the seriousness" of the terrorist attack, including holding in abeyance with immediate effect the Indus Waters Treaty of 1960 until Pakistan "credibly and irrevocably abjures its support for cross-border terrorism".

India also decided to close the Attari Integrated Checkpost - located along the international border between India and Pakistan in Punjab at a distance of about 28 km from Amritsar - with immediate effect.

"Those who have crossed over with valid endorsements may return through that route before May 1," said Misri.

Pakistani nationals will also not be permitted to travel to India under the SAARC visa exemption scheme. Any Specific Purpose Work Visa (SPES) visas issued in the past to Pakistani nationals are now deemed cancelled, and any Pakistani national currently in India under a SPES visa has 48 hours to leave India.

The Foreign Secretary also announced that the defence, military, naval, and air advisors at the Pakistani High Commission in New Delhi have been declared persona non grata and have a week to leave India.

Similarly, India will be withdrawing its own defence, navy and air advisors from the Indian High Commission in Islamabad, with these posts in the respective High Commissions deemed annulled.

"Five support staff of the Service Advisors will also be withdrawn from both High Commissions. The overall strength of the High Commissions will be brought down to 30 from the present 55 through further reductions, to be effected by May 1," said Misri.

The CCS, he said, was briefed in detail on the terrorist attack in Pahalgam, in which 25 Indians and one Nepali citizen were killed and several others sustained injuries.

"The CCS condemned the attack in the strongest terms and expressed its deepest condolences to the families of the victims and hoped for the early recovery of the injured. The CCS recorded its appreciation for such sentiments, which reflect zero tolerance for terrorism," the Foreign Secretary said.

Reviewing the overall security situation, the CCS also directed all forces to maintain high vigil.

"It resolved that perpetrators of this attack will be brought to justice and their sponsors held to account. As with the recent extradition of Tahawwur Rana, India will be unrelenting in the pursuit of those who have committed acts of terror or conspired to make them possible," remarked Misri.