Richard Branson's space company, Virgin Galactic, has been granted an operating licence to fly its passenger rocket ship with the world's first paying space tourists aboard once final safety tests are completed, the U.S. Federal Aviation Administration said on Monday.

The unprecedented licence covers all operations of Virgin Galactic's six-passenger, two-pilot SpaceShipTwo vehicle, including commercial passenger service, which according to FAA spokesman Hank Price is contingent on "certain terms and conditions" being met first.

Those requirements include verification of vehicle hardware and software "in an operational flight environment," the FAA wrote in an email.

The FAA, which oversees U.S. airline service and general aviation, is also the chief regulatory body for commercial space flight in the United States.

On Feb. 19, Richard Branson unveiled the new SpaceShipTwo, a six-passenger two-pilot vehicle meant to ferry people into space that replaces a rocket destroyed during a test flight in October 2014, in Mojave, Calif. (Lucy Nicholson/Reuters)

The new licence will be modified as Virgin Galactic supplies the FAA with additional data from the SpaceShipTwo flight test program, company spokeswoman Christine Choi said in an email.

The company has not yet announced a date for the start of passenger flights but is selling tickets for a ride aboard SpaceShipTwo at $250,000 US a seat. Commercial service is not expected to debut before 2017.

About 700 people have put down deposits for rides that will take them about 100 kilometres above Earth, where they will experience a few minutes of weightlessness and see the curvature of Earth set against the blackness of space.

Virgin Galactic's original SpaceShipTwo vehicle broke apart during an October 2014 test flight that killed the co-pilot and seriously injured the pilot, in an accident that was ultimately attributed to pilot error. Both were employees of Scaled Composites, a subsidiary of Mojave, Calif.-based Northrop Grumman, which built the vehicle.

The Spaceship Company, a Virgin Galactic sister firm also owned by Branson's London-based Virgin Group, built a new SpaceShipTwo, the second in a planned fleet of five, and took over the test flight program from Scaled.

The new ship, dubbed Unity, was rolled out of its hanger on Monday for its first taxi test at the Mojave Air and Space Port.

Today, we announced our FAA license & conducted <a href="https://twitter.com/hashtag/SpaceShipTwo?src=hash">#SpaceShipTwo</a> taxi tests (w/ help of friends <a href="https://twitter.com/LandRover">@LandRover</a>). Good day! <a href="https://t.co/pOtiE5RAv5">pic.twitter.com/pOtiE5RAv5</a> —@virgingalactic

Virgin Galactic plans to fly from Spaceport America, near Las Cruces, New Mexico. SpaceShipTwo will be ferried to an altitude of about 15,000 metres by a carrier jet known as White Knight Two and then released for an independent rocket ride beyond the atmosphere.

SpaceShipTwo is designed to glide back to the ground and land on a runway like a conventional airplane.