BBC News - Tom Espiner
Heathrow has been told to cut passenger charges for airlines each year until 2026 by the Civil Aviation Authority.
The regulator said the reduction in charges reflected the recent rebound in passenger numbers, but would still allow the airport to invest.
But Heathrow, which wanted the charges raised, said the move would undermine the delivery of key improvements.
The charges are paid by airlines, but can then be passed onto passengers via airfares.
The fees go towards operating terminals, runways, baggage systems and security.