Gatwick says it can handle 11 million more passengers a year by 2030 without needing a second runway.
The airport's publishing plans for its future later today.
Gatwick currently handles around 34 million passengers a year but says it could handle up to 45 million. One of their aims is to get more people to travel to the Sussex terminals by train.
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Monday night's weather for the west of the region
Monday night's weather for the east of the region
Michael Danaher, 50, has been sentenced to life in jail for murdering an antique book dealer - to steal a rare Wind in the Willows copy.