Islamabad: Pakistan International Airlines (PIA) is on the verge of a shutdown as it cancelled over 500 flights in the past 11 days due to the unavailability of fuel, ARY News reported.

ARY News is a Pakistani news channel.

PIA is facing its worst crisis in history as Pakistan State Oil (PSO) has cut its fuel supply over unpaid dues. The move forced the airline to cancel 537 flights since October 13.

On Thursday, as many as 49 domestic and international flights were cancelled from Karachi, Lahore, Islamabad, Quetta, Multan, Peshawar and other cities after the Pakistan State Oil (PSO) slashed its fuel supply to the PIA, sources said.

The flights include Karachi to Islamabad and Karachi to Turbat, all of which have to be called off.

Meanwhile, PIA's Chief Executive Officer (CEO) Amir Hayat has written a 'motivation letter' to the employees amid the financial crisis, closure of the flight operations and the ongoing privatisation process, as per ARY News.

Hayat asked all employees to maintain a concerted focus on ensuring organisational compliance through closely-knit teamwork ahead of the airline's privatisation.

PIA recently paid PKR 220 million (approximately USD 789000) to Pakistan State Oil (PSO) for a two-day fuel supply, ARY News reported on Saturday.

The PIA spokesperson said that the airline has paid PKR 500 million so far to the PSO for the provision of fuel, adding that the national flag carrier is making payments to PSO daily.

PIA is currently acquiring fuel for profitable routes including Saudi Arabia, Canada, China, Kaula Lumpur and others.