Banks is the biggest donor in British political history and a co-founder of Leave.EU, a campaign group for Brexit that was fronted by Nigel Farage during the 2016 referendum campaign. In November 2018, he was referred to Britain’s National Crime Agency (NCA), the body that investigates serious and organized crime, by Britain’s Electoral Commission. At the center of the investigation are $10.3m in loans made by Banks and his campaign to another anti-E.U. campaign group, Better for the Country, $3.8m of which were spent on campaigning during the referendum. The Electoral Commission’s referral of Banks to the NCA arose out of questions about the role played by a company based in the Isle of Man, an island off the coast of Great Britain outside of the Commission’s authority, in the flow of money between Banks, Leave.EU and Better for the Country. Banks had previously undisclosed meetings with the Russian ambassador to the U.K. during the Brexit and Trump campaigns, during which he was allegedly offered favourable deals to invest in gold and diamonds. Banks acknowledges the meetings but says he did not take up any offers.