The Airports Commission, led by RBS chairman Sir Howard Davies, said in July that it backed building a third runway at Heathrow airport. Prime Minister David Cameron and transport secretary Patrick McLoughlin have said that the government will respond to the Commission’s report in December.
A government decision in favour of Heathrow expansion would prove politically challenging for Cameron, who famously made a “no ifs, no buts” pledge in 2009 that there would be no third runway at the west London airport.
Meanwhile, Tory London mayoral candidate Zac Goldsmith has vowed to resign from his Richmond Park seat and trigger a by-election if the government supports expansion at the west London airport.
Labour’s London mayoral candidate Sadiq Khan also opposes expanding Heathrow, having backed expansion at Gatwick airport, instead.