Another foreign policy divide between Powell and Thatcher concerned their opinions and timings on the European Economic Community (EEC), as Thatcher was an enthusiastic supporter of Britain being members of the EEC in the 1970s and 1980s, including being one of the figureheads behind the victorious "Yes" campaign for Britain to stay in the EEC during the 1975 referendum, whereas Powell had been one of the figureheads of the losing "No" campaign to leave the EEC during the 1975 referendum. It was not until the late 1980s and into 1990 that Thatcher started expressing her increasing concern about the EEC's project to political and monetary union, whereas this was something that Powell had been warning about since the mid 1960s when he started openly opposing the EEC and the loss of British sovereignty that would result, showing Powell's stronger foresight into the matter.