The UK has begun the process of purchasing its own satellite navigation system for defence and critical national infrastructure purposes, according to reports. The Times says Boris Johnson and the chancellor, Rishi Sunak, signed off on the purchase of a 20% stake in satellite operator OneWeb on Thursday night, after the UK was unable to access the EU’s Galileo satellite navigation system because of Brexit. The prime minister agreed “to put up about £500m” of taxpayer money for the purchase, according to the Financial Times, which said the funds were part of a larger private sector consortium bid. The FT also said Johnson’s chief adviser, Dominic Cummings, was “instrumental” in pushing for the UK’s involvement in the bid. The government is seeking a system that will support mobile phones and provide vital location information for the military and businesses. OneWeb filed for bankruptcy in March in the US, where most of its operations are located, after failing to secure new funding. It is headquartered in the UK and has 74 satellites in orbit, with plans for hundreds more. Previously, the UK aimed to build its own global navigation satellite system, at a cost estimated by independent experts of £3bn-£5bn. In December 2018, Theresa May, then prime minister, saidBritain expected to work with the US and other “Five Eyes” partners.