After MPs voted to approve Heathrow Airport's expansion in Parliament, the path is still far from clear for the third runway to become a reality.
The National Policy Statement on Airports, including the building of the third runway was voted in by MPs by 414 to 119 in a late-night decision on Monday (June 25).
The following day, Transport Secretary Chris Grayling formally designated the policy to the Commons, essentially giving outline planning consent for the third runway plan.
"The designation of the Airports National Policy Statement marks a significant step forward," he told the Commons on Tuesday (June 26).
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"It provides the primary basis for decision making on development consent applications for a north-west runway at Heathrow Airport, clarifying what is required to enable the development of much needed additional airport capacity that is essential for trade and economic growth, whilst setting clear requirements to mitigate the impacts on local communities and the environment."
Heathrow Airport Limited has already carried out a voluntary consultation, the results of which are currently being compiled and used to inform the next stages for the development of their plan for the north west runway.
The plans revealed in their consultation in January were for a north-west runway which would extend several hundred metres over the M25 as well as new plants, station and terminal buildings and a new cargo facility.
The airport must now carry out another consultation, before they submit planning applications, which will be publicly examined by the Planning Inspectorate.
"Any application for development consent will of course be considered carefully and with an open mind based on the evidence provided, including through a public examination by the independent Planning Inspectorate, before a final decision is made," Grayling added.
Heathrow is hoping to have construction work start within three years, by 2021 and aim for the runway to be operational by 2026.
Directors at the airport are aiming to have as much construction work as possible completed off-site to minimise cost and disruption.
The area around the airport is expected to get 114,000 new jobs, while the number of people working at the airport is set to grow from 78,000 to 118,000.
However a court challenge has been proposed by Wandsworth, Richmond , Hillingdon and Hammersmith and Fulham councils in partnership with Greenpeace and mayor Sadiq Khan.
Greenpeace UK executive director John Sauven said: "If ministers don't want to uphold the laws protecting us from toxic fumes and climate change, we're going to ask a court to do that."
Hillingdon Council leader Ray Puddifoot added: Speaking after the vote, he said: "A third runway at Heathrow is simply untenable.
"This is a part of London where air pollution levels are already unlawful. The air quality will become significantly worse by adding a runway and all the traffic that goes with it.
"It seems that this is obvious to everyone apart from the Government.
"MPs should have used this opportunity to kill off this highly flawed project. Instead, the Government imposed a three-line whip on its MPs, and relied on other political parties for support, in order to secure the necessary number of votes in the House of Commons.
"In doing this, the Government has effectively prevented any democratic debate taking place in relation to a huge infrastructure project with such far-reaching consequences for public health and the environment.
"It is very unfortunate that MPs chose to ignore all the evidence which clearly points to the fact that a third runway is a very expensive white elephant."
