Timeline of Heathrow expansion delays

An announcement is expected on Thursday from the prime minister on the future expansion of Heathrow airport.

The Cabinet sub-committee, tasked with considering the government's response, is expected to meet and it is believed that ministers want the issue to be dealt with "quickly".

In 2009, before the Commission was set up, David Cameron said "the third runway at Heathrow is not going ahead, no ifs, no buts".

Newsnight's economics correspondent Duncan Weldon explains Heathrow's expansion delays.