Z  Energy is apologising to customers over a bad batch of aviation fuel it's imported.

Over 25 litres of this imported fuel is unusable and airlines are now on fuel rations. The Airline Representatives Board warns it could cause travel disruption.

The rations are expected to be needed until December 18.

Z Chief Executive Mike Bennetts says the ship was half unloaded when they discovered the issue, but they still can't put it in the supply chain as it poses a risk to the airlines.

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