An air ambulance carrying comedy king Umar Sharif took off from Karachi's Old Airport on Tuesday noon for the United States where he will receive medical treatment, reported 24NewsHD TV channel.

About an hour before the departure the legendary comedian was shifted from Aga Khan Hospital to the airport where the doctors carried out his medical check-up before boarding the plane.

Umar Sharif's Zareen Ghazal also accompanied him in the air ambulance.

Earlier, a spokesman of the Civil Aviation Authority told newsmen that the air ambulance was set to take off as all arrangements were in place.

Earlier, the veteran comedian was set to leave Pakistan on Monday morning but the air ambulance’s departure was delayed after Umar Sharif's health worsened.

Umar Sharif's son Jawad said the actor had again been shifted to the Intensive Care Unit after his health deteriorated delaying his departure for the United States on the directions of the doctors.

The flight was postponed after Umar's blood pressure dropped during dialysis.

Umar was set to travel on a German air ambulance to Washington, where he will be treated at the George Washington University Hospital.

The Civil Aviation Authority had allowed the aircraft to land in Pakistan on September 26, Sunday.

The comedian was to travel without his family. Umar's first wife and sons, Jawad and Fawad, were booked on a commercial flight by the Sindh Health Department.

Reporter Baseem Iftikhar