PM David Cameron's decision to remove transport secretary, Justine Greening, and aviation minister, Theresa Villiers, from their posts indicates the coalition could ‘ditch its promises' not to build a third runway at London's Heathrow Airport, Boris Johnson has warned.

The battle for London's aviation legacy – specifically the local environmental and economic impact of a ‘Boris Island' airport in the Thames Estuary or an extension of Heathrow – has become a growing source of dispute between London's mayor and Whitehall.