After considerable argument, the decision to proceed ultimately fell to an unlikely political expediency. At the time, the UK was pressing for admission to the European Economic Community, and this became the main rationale for moving ahead with the aircraft.[26] The development project was negotiated as an international treaty between the two countries rather than a commercial agreement between companies and included a clause, originally asked for by the UK government, imposing heavy penalties for cancellation. This treaty was signed on 29 November 1962.[27] Charles De Gaulle would soon veto the UK's entry into the European Community in a speech on 25 January 1963.[28]