 Dahlerus believed that they had succeeded.At the Nuremberg trials, the British prosecutor, Sir David Maxwell-Fyfe, was able to persuade the Swede that he had been badly misled by the German leaders, and that the discussion had no effect on the policy and actions of the Third Reich.On 25 August 1939, the British and Polish governments converted the unilateral declaration of support offered by the British government into a mutual assistance pact.