NEW DELHI: After a server shutdown that interrupted flight operations for several hours, national carrier Air India has managed to restore its system.

"Between 3:30 to 4:30 am today, passenger services system of Air India that is run by SITA was taken for maintenance and after that it remained down till 8:45 am, it has just come back. System restored. During the day we will see consequential delays," Air India chairman Ashwani Lohani was quoted as saying by news agency ANI.

Flight operations of the national carrier have been affected across India and abroad since early this morning due to a problem in the airline's main server. The national carrier said that "breakdown" in its server system has affected its flights all over the world.

Passengers complained that the Air India operations have been affected since 3:00 am. "

The problem has been attributed to shutdown of SITA software. "The SITA server is down. Due to which flight operation is affected. Our technical teams are on work and soon system may be recovered. Inconvenience is deeply regretted," an Air India spokesperson was quoted as saying by news agency ANI.