A £33billion plan to move the M25 to make way for Heathrow’s third runway has been backed by ministers.
The Transport Secretary on Wednesday rejected a rival proposal from Arora Group, saying the airport’s own plans were "the most credible and deliverable option".
Heidi Alexander did concede that Heathrow’s scheme “requires major works to the M25” but it would mean “the acquisition of fewer residential properties around the airport” than the other option.
The proposals involve building a 3,500-metre runway and require a new M25 tunnel and bridges to be built 130 metres west of the existing motorway.
The Arora plan, put forward by a group led by hotel tycoon Surinder Arora, was for a shorter, 2,800-metre runway that would not require diverting the major London ring road.
But in a written statement to Parliament, Ms Alexander said the proposal would still have "a considerable impact" on the motorway.
Motorists have already suffered delays at the M25/A3 junction for years as the roadworks there have taken longer than expected.
A Heathrow spokesperson welcomed the decision, saying expanding the airport "will mean more connectivity, increased trade, improved passenger experience and a huge economic boost for the British businesses that will help design and build it".
But the spokesperson added that "further clarity" was needed on how the next phase of the project would be regulated, calling for "definitive decisions" from Government and the Civil Aviation Authority by mid-December.
Mr Arora said his group "accepts today's announcement" and still hoped to be chosen as the "promoter" of the third runway, rather than Heathrow Airport, adding that competition was "absolutely imperative to keep costs under control at the airport".
The planned third runway is estimated to cost £33 billion, including £1.5 billion on moving the M25, and is expected to be fully privately financed.
It will see Heathrow's capacity increase to 756,000 flights and 150 million passengers per year.
The Government aims to make a decision on a planning application for Heathrow's expansion by the next election, with the third runway becoming operational by 2035.
Ms Alexander said Tuesday's decision would "allow a decision on a third runway plan this Parliament which meets our key tests including on the environment and economic growth".
She added: "We're acting swiftly and decisively to get this project off the ground so we can realise its transformational potential for passengers, businesses and our economy sooner."
The proposals will be subject to further consultation as the Government overhauls the Airports National Policy Statement that governs planning decisions for airports.
The Transport Secretary has also pledged to consult the independent Climate Change Committee on the expansion to ensure it is consistent with the Government's commitments to reduce carbon emissions.
