UK firms currently working on the EU’s Galileo satellite navigation system could be cut out of existing contracts under a no-deal Brexit, Government technical papers say.
The 10 billion euro programme has been at the heart of an access row between the UK and the EU that prompted Theresa May to announce £92 million seed funding for a British rival in August.
Firms have already been warned they face blocks to bidding for new work on the programme, a rival to the US GPS system.
But a technical paper released by the Department for Business, Energy & Industrial Strategy (BEIS) went further, warning the UK would “no longer play any part in the development of Galileo” or the related European Geostationary Navigation Overlay (EGNO) system.
It added: "This means that UK-based businesses, academics and researchers will be unable to bid for future EU Global Navigation Satellite System contracts and may face difficulty carrying out and completing existing contracts.
"For example, it may not be possible for businesses or organisations which currently host Galileo and EGNO ground infrastructure to continue to do so."
Britain is keen to remain part of Galileo after Brexit if a deal can be agreed but the EU is insisting full membership of the programme is only open to member states.
The row between Britain, the European Space Agency and European Commission centres on the level of access the UK will have to the Public Regulated Service (PRS) – a navigation and timing signal intended for use by government agencies, armed forces and emergency services.
The UK insists for its involvement in the system to be worth continuing, it must be able to have detailed technical information about the PRS signal in order to rely on it for military purposes, something the EU is only prepared to grant to members of the bloc.
In August, Theresa May confirmed £92 million would be used to develop plans for an alternative satellite navigation system amid doubts over the future of British involvement.
The Prime Minister said the UK was clear it would withdraw UK support for Galileo unless it received assurances of close collaboration post-Brexit, adding: "This is not an idle threat to achieve our negotiating objectives."
Thursday’s technical paper added: "In the unlikely event of the UK leaving the EU without a negotiated agreement, the majority of position, navigation and timing services provided by Galileo and European Geostationary Navigation Overlay will continue to be freely available to all UK-based users.
"The Public Regulated Service will not be available to the UK; however, this is not expected to be completed until the mid-2020s and will not have immediate impact on users."