Heathrow airport protest is part of a long runway of shifting debates

Since a white paper was published 12 years ago, arguments over environmental issues, as well as land ownership, have been constantly on the move

It was 3.30am on Monday morning when 13 people, one dressed as a polar bear, cut through the wire at Heathrow airport and chained themselves to its northern runway. The runway's three-hour closure has resulted in 13 cancelled flights, around 1% of the airport's daily landings and departures.

Direct action group Plane Stupid said its protest aims to highlight "the terrifying consequences of flying", by bringing climate change back into the debate on airport expansion in the UK. It was reignited two weeks ago when the Airports Commission published its "clear and unanimous" recommendation for a 17bn expansion plan, including a third runway, at Heathrow.