An official announcement could happen as early as this week, according to the insiders. It's not clear when the country would want an operational network, although that's likely to depend on the results of the initial study.

Any self-developed network is likely to be expensive (one estimate put it at £3 billion), and it's easy to foresee opposition to the plan if made official. The country does have strong incentives to build its own satellites instead of relying on others, though. The UK might not have access to Galileo's most accurate encrypted signal, and the US reserves its most accurate GPS data for its own military. An in-house system may be the only way to get the kind of location accuracy and security British armed forces would want.