Two special flights had left for Toronto on April 2, at the behest of the Government of Canada.
The flights will depart Toronto for Turkey, according to the PIA spokesperson, and will land at Istanbul airport to carry back 170 stranded Pakistani nationals there.
When the need arises, he said, passengers will be screened and transferred to quarantine.
Pakistan has suspended flight operations in a bid to control the spread of coronavirus. The flights were scheduled to resume as of April 4 but the date has been extended to April 11. Domestic flights were also suspended to prevent the virus from spreading among provinces.
Only special and freighter flights were exempted from the ban.