Pakistan had shut its airspace in February, resulting in a significant rise of Air India's operating costs on flights connecting Delhi to Europe.
The disinvestment-bound carrier, which is incurring Rs 15 crore loss per day, has huge dues towards oil companies and AAI, among others.
The incident evoked memories of the air tragedy at the same airport on May 22, 2010, when an Air India Express flight overshot the table-top runway and plunged into a gorge, killing 152 passengers.
India-Dubai is considered one of the most lucrative sectors as demand is always very high on the route due to high business as well as leisure travel.
The average duration of delay on these 137 flights of Sunday would be of 3 hours, the airline's spokesperson said.
Air India CMD Ashwani Lohani had issued a similar direction to pilots in May 2016. The current advisory is a reminder to the staff, in line with the 'mood of the nation'.
Following the threat call, Chhatrapati Shivaji Maharaj International Airport in Mumbai was put on high alert and the security there was beefed up.
According to a top executive, the airline is planning to use its aircrafts for half an hour to one hour more per day.
Najaf is renowned as the site of the tomb of Caliph 'Ali ibn Abi Talib, who is revered by all Muslims but is considered to be the first Imam of the Shias.
The passengers reached Male 10 hours late after a different aircraft and crew were arranged.
Haj subsidy is set to be scrapped from 2018 with the Centre deciding to go ahead with the recommendation for its immediate abolition by a special committee set up in January this year.