Subsequent to De Gaulle's November 1967 veto of Wilson's EEC application, senior British ministers still saw the European question as having considerable importance. Shortly before his departure from the role of Foreign Secretary, George Brown reported to the Defence and Oversea Policy Committee that the ructions over Article 3 of the NPT would be "particularly awkward for us as potential members of EURATOM and the E.E.C." De Gaulle's second "Non!" only served to postpone Britain's membership of the EEC, as Edward Heath's Conservative government successfully campaigned for accession, which took place in 1973.

Before and after de Gaulle's November 1967 veto of Britain's second EEC application, Britain's position in Europe and its relationships with existing EEC states shaped the UK's role in the NPT negotiations. Prior to 1967, London canvassed opinion in EEC capitals, particularly in Bonn. As the NPT negotiations wound their way through the Eighteen Nation Committee on Disarmament (of which the United Kingdom was a member) in 1967, British representatives reported deep-seated concerns in Bonn, Brussels, the Hague, Luxembourg City, Paris, and Rome that a non-proliferation agreement might threaten the continued functioning of EURATOM, namely that its power might be subsumed into the IAEA, opening non-nuclear-weapon states (NNWS) up to commercial espionage conducted by inspectors representing the nuclear-weapon states (NWS).