Heathrow’s expansion plans were left up in the air when opponents won a Court of Appeal challenge in February.

Supreme Court judges will deliver their ruling on the airport’s appeal on Wednesday.

This will be the latest twist in a saga that began 17 years ago.

December 2003: A Government White Paper recommends a third runway is built at Heathrow.

November 2007: The Government publishes expansion plans. It says the new runway could be in operation by 2020.

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.

October 2009: Opposition leader David Cameron tells a public meeting in Richmond, south-west London, that expansion of the nearby airport will not go ahead, saying “no ifs, no buts”.

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 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 to the Supreme Court.

October 2020: A panel of five Supreme Court justices hear the challenge.

December 2020: The Supreme Court rules in Heathrow’s favour, finding the Government’s decision was lawful.