Over the following years the barbed wire and mesh barrier that was constructed overnight was gradually replaced with a virtually impregnable ring of reinforced concrete that ran 155km around West Berlin.

SS-Obergruppenführer Reinhard Heydrich called the meeting in the Berlin suburb, in which he outlined the deportation of European Jews to extermination camps in Poland where they would be systematically murdered.

While the speech effectively recognised East Berlin as part of the Soviet Bloc, it also reaffirmed America’s commitment to defend West Berlin against Communist expansion.