Plans to expand London's other airports are already further along than Heathrow's and have in the past been viewed as an alternative to a third Heathrow runway. Work is set to start this year to expand capacity at Stansted's terminal. The government is due to make a decision on Gatwick airport by 27 February.

The third runway is part of its drive to lift the U.K. economy out of a long period of stagnation, Treasury chief Rachel Reeves said in a speech on Wednesday.

It is the rich and the corporations who will take the lion’s share of the benefits from Labour’s and all airport expansions, while the poorest around the world pay the costs.