UPDATE: The fog has now lifted and flights are able to land and take off again, however there are delays.
EARLIER: Fog is preventing planes from landing and taking off at Newcastle Airport this morning.
The early morning Jetstar flight from Melbourne was diverted to Sydney, while a REX flight from Sydney was forced to turn back.
A Virgin Australia flight from Brisbane is currently circling off the coast, waiting for the fog to lift.
While a Qantaslink service to Brisbane is stuck on the tarmac, unable to take off.
A Newcastle Airport spokeswoman says passengers should check with their airlines.