Foreign Minister Julie Bishop says two Royal Australian Air Force planes on their way to South Sudan may be used to evacuate Australian citizens.
The planes are being sent initially to help transport extra United Nations troops being sent to South Sudan, amid continuing fighting between rival groups.
Ms Bishop says hundreds of Australians still believed to be in South Sudan are being urged to leave on commercial flights as soon as possible.
But she told Kerri Worthington the two Australian planes could be used to evacuate some of them if necessary.
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