Heathrow faces a formal complaint to the Competition and Markets Authority over airport expansion.
The complaint has been lodged by Heathrow Hub which is proposing an alternative extended northern runway scheme instead of building a new third runway at the airport.
Submitted by legal advisers DAC Beachcroft, Heathrow Hub claims Heathrow abused its dominant market position by “effectively and unfairly vetoing” the extended runway option.
Heathrow has publicly claimed it did not veto the extended runway, saying that the Airports Commission, while deeming the extended runway viable, preferred its own north-west runway scheme.
Parliament is due to vote on Heathrow expansion this summer and Heathrow Hub has already submitted a revised draft National Policy Statement to the Department for Transport so its scheme could be implemented quickly.
Heathrow Hub director Jock Lowe said: “Our scheme is cheaper, quicker, quieter and easier to build than the third runway.
“After years of trying to work co-operatively with Heathrow Airport and the Department for Transport, we have decided it is time to take the gloves off.
“The consequence of Heathrow’s veto and the flawed process run by the DfT is that consumers and airlines are being saddled with its unnecessarily complex, noisy and expensive third runway which will take years to build.
“We hope the CMA will inject some rigour and common sense into the process so that this vital piece of national infrastructure can be delivered quickly and cheaply while taking account of the important environmental impacts on local communities.”