The building of a new runway at Heathrow is being opposed by British Airways owner International Airlines Group.
Chief executive, Willie Walsh, said the costs of the project do not make sense for BA, the biggest airline at the London hub.
“We think the costs associated with the third runway are outrageous and certainly from an IAG point of view we will not be supporting it and we will not be paying for it,” Reuters reported him as saying.
Heathrow is operating at full capacity and wants to build a third runway but faces significant political challenges to do so.
An expanded airport would be partly paid for by higher charges to airlines.
“We’re not going to support something that increases our costs,” Walsh added.
Responding to Walsh’s comments, Gatwick chief executive, Stewart Wingate, said: “It is no surprise British Airways have come out today against expansion.
“For the huge costs of a third runway at Heathrow you could build Gatwick, have all the benefits and billions left to invest around the country.”
He also claimed that “buried deep” in the Airports Commission report is a suggestion that a third runway would reduce rather than increase domestic connections to the UK.
“This blows a hole straight through the heart of Heathrow’s central claim to be the airport for the whole of the UK,” Wingate said.
“Choose Heathrow and it will be Groundhog Day – nothing will happen. Choose Gatwick and Britain can finally get on with it.”