"The total loss of revenue already caused to Air India due to prolonged strike by the pilots is approximately Rs 600 crore," he told the Rajya Sabha in a written reply.
He said a section of Air India pilots represented by Indian Pilots Guild started reporting sick from May 7, in protest against the management's decision to train pilots of erstwhile Indian Airlines to fly Boeing 787 Dreamliner aircraft.
The minister said due to the strike the national carrier had to restructure its operations and operate 39 international flights against 46.
He also informed that Air India management has derecognised the pilot's union and terminated the services of 98 pilots.
In reply to separate question, Singh said, "No recruitment action has been initiated by the Air India management."
He also said Justice Dharmadhikari Committee had given its recommendations and the government has sent it to Air India management for implementation.
"Air India has also prepared a Voluntary Retirement Scheme for its employees," Singh said.