RADICAL plans for a high-speed rail link from London to the north via Heathrow have taken a step forward with the formation of a development company to start work on the project.

Heathrow Hub has been set up by Arup, the engineering and professional-services group that mooted the scheme. The plan has gained impetus in recent months thanks to the public backing of senior Labour and Conservative politicians.

Gordon Brown is tipped to give the go-ahead for construction of a third runway at Heathrow this week, despite opposition from Cabinet members, green campaigners and local authorities near the airport.

Brown is expected to try to mollify opponents by setting strict environmental criteria for the new runway, including improved rail links.

The Arup plan, revealed by The Sunday Times a year ago, would see a TGV-style rail line running west of London via Heathrow and then turning north. A key part of the scheme is a large new rail station at Heathrow – the Heathrow Hub – that would allow up to 30m passengers a year to make swift transfers between the airport and trains running to London, Birmingham, Scotland – and to Paris via the Channel tunnel high-speed line.

Arup has taken the plan a step further with the creation of a development company. Documents at Companies House show several of its most senior employees are directors, as is Ian Trehearne, a partner at top City law firm Berwin Leighton Paisner.

Arup declined to comment yesterday, but it is understood the company will seek to raise about £10m from outside investors to pay for detailed feasibility work. The engineering firm used a similar approach to develop its plans for the Channel tunnel rail link in the late 1980s, setting up a group that formed the basis of today’s London & Continental Railways.

Senior politicians from both leading parties have championed the Arup rail plan in recent months. In October, Conservative leader David Cameron came out against the construction of a third runway at Heathrow, saying the high-speed rail plan would reduce the need for additional flights.

Last week Lord Adonis, who is developing new transport policy for Labour, told The Sunday Times the Heathrow Hub was “an attractive idea”. Unlike Cameron, he said the rail scheme would not do away with the need for a new runway but complement it.

Business leaders and unions are expected to call tomorrow for the government to press ahead with the third runway, saying it is vital for the economy. Their announcement is likely to coincide with a protest by antirunway campaigners at Heathrow’s Terminal One.

If given the green light by Brown, a new runway would be unlikely to open before the end of the next decade.

Expansion of Heathrow is the priority for BAA, the airport’s owner.

The group, controlled by Spanish infrastructure giant Ferrovial, owns and runs London’s other two big airports, Gatwick and Stansted.

Gatwick is up for sale, and the Competition Commission, which is investigating airport ownership, has indicated that it will demand the sale of Stansted as well. BAA has said it will oppose the move.

Indicative bids for Gatwick are due in by January 19.

Times Recommends

• C&G axed - 1,660 jobs to be lost
• UK house prices rise 1.1% as buyers return
• Mixed reaction to US banks repaying bailouts