Heathrow expansion plans have been left up in the air again after opponents won a Court of Appeal challenge.
The ruling, based on concerns about climate change, is the latest twist in a saga which began almost 17 years ago.
December 2003: A Government White Paper recommends a third runway is built at Heathrow.
November 2008: London mayor Boris Johnson, an opponent of Heathrow expansion, orders a feasibility study for an alternative plan for a new airport on an artificial island in the Thames estuary.
January 2009: Prime Minister Gordon Brown backs a third Heathrow runway despite strong opposition from local residents, environmental groups, neighbouring councils and Labour backbenchers.
May 2010: Labour loses the general election. The new coalition government of Conservatives and Liberal Democrats immediately scraps the third runway proposal.
March 2012: Supporters of the plan are given renewed hope when Mr Cameron and Chancellor George Osborne say there is a need for airport expansion in south east England.
September 2012: An independent commission on future airport policy is set up by Whitehall, chaired by Sir Howard Davies.
July 2015: The commission, which dismissed the ‘Boris island’ plan, recommends that a new runway should be built at Heathrow rather than Gatwick.
June 2018: MPs vote in favour of expansion by a large majority.
February 2020: Campaigners win a Court of Appeal ruling over the third runway on environmental grounds. Heathrow Airport says it will appeal against the ruling to the Supreme Court.