Pakistan suspended on Thursday all flight operations to neighbouring Iran after two coronavirus cases were confirmed in Karachi and Islamabad.
Iran has reported approximately 150 confirmed cases and 11 deaths.
The federal aviation ministry said the ban has been in effect since midnight.
Pakistan already sealed the border to Iran in Taftan on Sunday and stopped pilgrims from travelling to Iran.
Both confirmed coronavirus cases in Pakistan were of people who had recently travelled to Iran.
In Afghanistan, three cases have also been confirmed and all three recently travelled to Iran.