I NOTE with interest your article regarding the decision by CityJet to reduce the frequency of flights between Dundee and London City ("Kelly's fury as flight is axed", The Herald, October 1) .

Flight schedules are determined by airlines based on a number of factors including forecast passenger demand and aircraft availability. As the airport operator, Highlands and Islands Airports Ltd (HIAL) does not decide when flights should operate, nor does it set the cost of airline tickets. These are entirely commercial matters for airlines. Nevertheless, HIAL has worked closely with CityJet and continues to support this important route in a number of ways.

However, it is fair to say that our efforts to support the route have been hampered by the impact of Air Passenger Duty (APD). While APD is exempt on all departing flights from the Highlands and Islands, it applies to flights to and from Dundee. APD disproportionately affects smaller regional airports and makes it more difficult for airports such as Dundee to compete for new business.

With Scotland's busiest airport, Edinburgh, within easy reach of Dundee, the challenge is even greater.

We will continue to press the UK Government to do more to support airports such as Dundee.

Inglis Lyon,

Managing director, Highlands and Islands Airports Ltd, Inverness Airport, Inverness.