Gatwick has been campaigning to be free of CAA regulation saying it was a move to protect passengers when the British Airports Authority controlled Heathrow and Stansted as well.
It wants to be free of being told how much it can raise prices for passengers to use the airport.
This has been rejected. The airport argues the money spent to having to deal with the CAA would be better invested in the airports and could cut costs.
The CAA disagree but today Gatwick say the small rise in fees suggested will not give it the money it needs to improve the airport for passengers.
In a statement Gatwick Airport said: "We believe this price level is based on unrealistic CAA assumptions, including on traffic growth, efficiency gains and financing."