Almost half the number of flights that use Heathrow are for UK or near European destinations, HACAN said. Even the latter can be reached quickly by rail following the launch of high-speed Eurostar services from St Pancras this week, it argued.
Chairman John Stewart said: "The government should take advantage of the opportunities offered by the faster Eurostar journeys to limit the number of landing slots available to short-haul flights." This would allow long-distance flights to be added without the need to expand the airport, he said.
The British Air Transport Association said a one-size- fits-all approach to travel to the continent and in the UK is not viable. High-speed rail has had some impact since it started operating from Waterloo, general secretary Roger Wiltshire noted, but journey times often necessitate an overnight stay.