Virgin Galactic also revealed on Tuesday that up to 38,000 people from 126 countries have paid a deposit for a seat on one of its manned commercial flights, including a core group of 100 "founders" who have paid the initial $200,000 cost of a flight upfront.
Virgin Galactic is planning to begin flights in late 2008 or early 2009.
New Mexico Economic Development Secretary Rick Homans said that construction of the spaceport, to be built largely underground in the south of the state near the White Sands Missile Range, could begin in early 2007, depending on approval from environmental and aviation authorities.
Virgin will have a 20-year lease on the facility, with annual payments tied to $1 million for the first five years and rising to cover the cost of the project by the end of the lease.
"Experts predict that thousands of jobs and hundreds of millions of dollars of private investment will be created in the next 20 years as the private sector develops new commercial markets in the space industry in New Mexico," Homans said in London.
"Virgin is the beginning and many other space companies will follow."
American Gregory Olsen came
back from a space trip in October
Virgin Galactic said it had chosen New Mexico as the site for its headquarters because of its steady climate, free airspace, low population density and high altitude. All those factors can significantly reduce the cost of the space flight programme.
The spaceport, to be located some 25 miles south of the town of Truth or Consequences, will be constructed 90% underground, with just the runway and supporting structures above ground.
Stephen Attenborough, the Virgin Galactic executive in charge of marketing the space flights, said that the 100 founder members were committed to "stepping up to the plate" and boarding a flight early in the operations.
"Many of the others will need to wait until the price comes down and will want to wait for proven reliability and safety," he said.
Trevor Beattie, a London-based advertising director who paid for his ticket within days of Branson announcing the company's launch after dreaming of going to space since watching the 1969 moonwalk, said he was not concerned about safety.
"My only concern is that the longer they leave the launch, the more likely we all are to be hit by a bus," Beattie said.
SpaceShipOne, the first privately
manned rocket to reach space
Branson formed Virgin Galactic after watching SpaceShipOne, a craft designed by Burt Rutan and funded by Microsoft Corp co-founder Paul Allen, become the first privately manned rocket to reach space last year.
SpaceShipOne went on to win the $10 million Ansari X Prize with two suborbital flights in five days from Mojave, California.
Virgin Galactic has a deal with Rutan to build five spacecraft licensing technology from Allen's company, Mojave Aerospace Ventures.
Virgin Galactic plans to operate its initial flights from the Mojave base in advance of the projected opening the New Mexico spaceport in late 2009 or early 2010.
Virgin Galactic also unveiled its logo - the pupil of an eye incorporating an eclipse.
Branson's iris will be used for the final design.
Branson is due to join New Mexico Governor Bill Richardson in the US on Wednesday to unveil the spaceport plans.