In another move following the April 22 terrorist attack in Pahalgam that left 26 people dead, India closed its airspace to aircraft registered in Pakistan and those operated by Pakistani airlines. A NOTAM (Notice to Airmen) issued on Wednesday confirmed that Indian airspace will remain shut for Pakistani aircraft from April 30 to May 23.ET had reported on Tuesday that India was considering the move after Pakistan closed its airspace to Indian carriers on April 24th in retaliation to New Delhi’s steps post-attack. The decision, seen as part of a broader response to the attack, will impact flight operations of Pakistan International Airlines (PIA), which uses Indian airspace to access Kuala Lumpur for three flights a week. However, the move is seen as largely symbolic as the concerned flights from PIA have been avoiding the route through the Indian airspace since April 24th, two days after the attack. Officials familiar with the matter had told ET that India is also considering a ban on Pakistani ships from calling at Indian ports, which could further strain bilateral ties.Meanwhile, within 48 hours of the attack taking place, India initiated several diplomatic and economic countermeasures. Last week, the Cabinet Committee on Security suspended the Indus Waters Treaty of 1960 until Pakistan verifiably ceases its support for cross-border terrorism. In addition, India revoked visas issued to Pakistani citizens, shut down the Attari border crossing, and barred entry under the SAARC Visa Exemption Scheme.Impact of Pakistan's moveWhen Pakistan closed its airspace to Indian carriers, it caused widespread disruption across several major international routes. Flights connecting India to North America, Europe, Central Asia, and the Middle East have been most affected, with airlines forced to take longer detours over the Arabian Sea and southern Iran. This has resulted in increased flight durations, higher fuel consumption, and potential delays or cancellations. Airlines such as Air India and IndiGo have already issued advisories, urging passengers to check schedules for updates.Most affected international routes 1. India–North America Routes Delhi to New York (Air India AI101): Flight time increased by up to 2 hours. Mumbai to Toronto (Air India AI187): Approximately 2 hours added due to detours. Delhi to San Francisco (Air India AI173): Longer routing may require technical stops or payload adjustments. 2. India–Europe Routes Delhi to London (Air India AI111): Around 1 hour added to flight time. Mumbai to Frankfurt (Air India AI757): Longer travel times causing potential delays. Delhi to Paris (Air India AI143): Approximately 1 hour added to flight duration. 3. India–Central Asia Routes Delhi to Almaty (IndiGo 6E1807): Flights canceled due to airspace restrictions. Delhi to Tashkent (IndiGo 6E1805): 80–90 minutes longer due to rerouting. 4. India–Middle East Routes Delhi to Dubai (Air India AI995): Delays of 30–45 minutes. Amritsar to Sharjah (IndiGo 6E1428): Schedule adjustments due to airspace avoidance.