Sir Richard Branson’s space tourism company has signed a deal with Nasa to help get its flights off the ground, MPs heard today.

Will Whitehorn, president of Virgin Galactic, confirmed that the company had signed a co-operation deal with the US space agency at midnight in an unprecedented collaboration.

He told the Commons Science and Technology Committee that the firm would benefit from the agency's expertise, while Nasa would use seats on its flights for early astronaut training.

Mr Whitehorn said: “They obviously believe in it and who am I to question them?”

Virgin Galactic will offer members of the public the chance to experience a few minutes in space in a $200,000 two-and-a-half hour flight from 2008.

The company’s rocket-powered ships will be launched from adapted jet aircraft at 50,000 feet, reducing fuel costs and environmental impact. Each flight will carry six “astronaut passengers” and two pilots.

The sub-orbital rocket flight will be brief, but will include the chance to experience weightlessness and to see the earth from space. The ship will “float” to earth like a shuttlecock using “feathering” technology, Mr Whitehorn said.

Professor Stephen Hawking, the wheelchair-bound physicist, is booked on one of the first flights, courtesy of sponsorship from Sir Richard.

Mr Whitehorn said that fares for passenger flights into space would tumble from the $200,000 (£100,000) now advertised. “We believe that after five years we can get that cost down to $75,000 and after nine years to $50,000 or £25,000.”

On the flights’ environmental footprint, he said: “It can get eight people into space for an environmental effect less than a single business class ticket to New York.”

But Jeff Gazzard, of the Aviation Environment Federation, pointed out that transatlantic flights are an inevitable extra for British passengers.

The flights cannot operate from Britain under current legislation and will fly from the Mojave Spaceport in California, where space tourism flights are legal under a recent US Act.

Mr Whitehorn called on the Government to pass similar legislation to allow space tourism flights to operate from the UK. He pointed to recent high-level interest in Sweden and Dubai, and said the country risked missing “a massive opportunity”.

He said that Virgin Galactic would enable significant technological developments, benefiting science and the economy, as well as its customers.

However, Mr Gazzard, dismissed the firm’s claims to be leading the way in aerospace technology. He said: “I know the calibre of the people involved in this project. They are cutting edge world leaders, but that is not to say this is a cutting edge project.”

He went on to slam the project’s wider value: “It is a bit like going to the opening of a car door. I can see no benefit to anybody apart from Virgin branding.”

Dr Patrick Collins, director of Future Space Consulting, meanwhile, said that sub-orbital space flights could cost just £3,000 within ten years with investment in alternative aircraft technology first developed by the military during the 1950s.

Sub-orbital flights cross the 100km line above sea-level that defines space but do not enter orbit or experience the dramatic re-entry faced by orbital space missions.

Times Recommends

• Foxy Knoxy snared by her lust and her lies
• Britain is the land of the shrinking family
• Zac Goldsmith: Not such a green god