The Kuala Lumpur High Court ordered the release after both sides said they had reached an amicable settlement of the dispute, involving two planes leased to PIA, a lawyer for the airline said.
The first flight PK9702 will carry more than 250 passengers from Manchester to Islamabad and the next flight PK9785 will airlift passengers from Islamabad to London are scheduled for Aug.14 and 15 respectively, PIA spokesman Abdullah Hafeez said.
The pilots were suspended earlier this month after authorities in Pakistan discovered that up to a third of the country's pilots may have falsified their qualifications.
In June, Aviation Minister Ghulam Sarwar Khan disclosed the details of the inquiry, saying that 262 pilots having false credentials will be grounded. Of them, he said, 141 were from PIA, nine from Air Blue and 10 from Serene Air.
PIA issued a statement citing chief executive Arshad Malik as welcoming the ICAO conclusion as a positive development for aviation in Pakistan, which would pave the way for the resumption of PIA flights to Britain and the rest of Europe.