The acting foreign minister of Libya's rebel government cancelled a trip to Qatar on Saturday after Saudi Arabia refused to allow his plane to use its airspace, Cairo airport officials said.

The officials said Ali al-Isawi's plane stopped in Cairo to refuel on its way from Rome when Saudi Arabia informed the crew that they would not be allowed to fly through its airspace.

Isawi returned to Benghazi, the rebel's stronghold in eastern Libya, after waiting several hours in Cairo, they said. They did not explain why Saudi Arabia barred the plane.

Qatar and the United Arab Emirates are the only Arab countries that joined a NATO coalition in enforcing a UN sanctioned no-fly zone over Libya after leader Moamer Khadafi appeared poised to win back rebel controlled territories.