Astrium has also been named prime contractor for the Alphasat project, which is supported by the European Space Agency (ESA) and the British space agency BNSC, with financial support for the public/private finance bid from the South East England Development Agency (SEEDA), the East of England Development Agency (EEDA) and the London Development Agency (LDA).

The Alphasat I-XL satellite will deliver high bandwidth services across Europe, Asia, Africa and the Middle East, and the "bird" will be one of the biggest and most sophisticated commercial satellites built to date. Astrium says it will have the capability to supply five times the communications capacity of one of the existing Inmarsat Type 4 satellites.

The spacecraft will be the first to be built under the ESA's Alphabus project, developed to compete in the global commercial satellite business.

The spacecraft's chassis and final assembly will be undertaken at Astrium's other European facilities, including Portsmouth in England, and those of its major partner in the project, Thales Alenia Space.

It will have a next generation digital processor and drive mechanism developed by Astrium U.K. with support from the British National Space Centre, which coordinates the UK's civil space programme.

The service offered by the monster satellite will augment Inmarsat's existing Broadband Global Area Network (BGAN) service.

The contract win will bring economic benefits and retain more than 500 technology jobs in the south east of England during the development and operation of the satellite, said the South East England Development Agency.

Andrew Sukawaty, CEO Inmarsat said:"Alphasat will enable us to offer improved services through greater capacity, better quality communications and faster download times to existing and future Inmarsat customers. And with the key technology on the satellite developed and manufactured in the UK  it again proves that Britain is at the forefront of the new space race."