London mayor outlines plans for £50bn, four-runway airport and transport hub in Thames estuary.

The mayor is submitting detailed proposals for three potential sites to the Airports Commission: one on the Isle of Grain in the Thames estuary, an offshore estuary option, and a transformed Stansted.

Heathrow is Europe’s No. 1 air hub, attracting 69.4 million passengers in 2011, while London Gatwick is the world’s busiest single-runway airport, both are running close to capacity.

At the same time, he will call for the closure or scaling down of Heathrow, claiming the land could sustain a thriving new London borough.

Heathrow and local councils have argued that building a new hub would force the airport out of business, causing substantial job losses in the area.

Johnson’s camp will acknowledge that Heathrow would have no future as an airport under their plans.

But he will argue that its transport links make it an ideal location to develop thousands of new homes and businesses in the heart of London’s affluent western suburbs.

A Heathrow spokesman said: “It seems extraordinary that any mayor of London would propose forcibly buying and then closing Heathrow.

“The mayor’s proposals would leave 114,000 people facing redundancy, cost taxpayers more and take longer to deliver than building on the strength we already have at Heathrow.”

Heathrow will respond on Wednesday with a series of specific options for a third runway, none of which replicate the plans scrapped by the coalition in 2010.

One proposal is believed to be a new runway towards Stanwell Moor to the south-west of the existing airport, although the most realistic option is still to the north, where land was safeguarded for a third runway.

The village of Sipson, earmarked for demolition before the 2010 election under the third runway proposals, will apparently not be reprieved. It is understood the village features in at least one of the options being proposed.

Ahead of the Friday 19 July deadline for submissions to the Airports Commission, Heathrow intends to place the onus on the government – or at least commission chair Sir Howard Davies – to pick the preferred option. Heathrow insists that choosing sites for airport expansion is a “political decision”.

The Heathrow third runway plans will include estimates of costs, of the number of homes that would  be demolished and the noise impact on surrounding neighbourhoods.

Heathrow will also signal that a fourth runway should not be necessary for decades, in an attempt to head off Johnson’s demands for a four-runway hub and to limit any public backlash from London residents threatened by noise from new flight paths.

The airport and the mayor share the view that expansion in the south-east is essential to safeguard the UK’s position as a leader in international aviation. They believe England needs extra capacity at a larger hub airport, with enough connecting flights and passengers to make long-haul routes feasible.

This has the backing of some business leaders, who argue that tapping new export markets in the developing world is more difficult without direct flights to destinations in Russia, India, Brazil and China.

However, that position is disputed by other airports. Gatwick, for instance, will submit plans for its own second runway to the commission, arguing for a “constellation approach” to airport capacity around London.