 On 31 March 1939, Britain extended a guarantee to Poland stating that "if any action clearly threatened Polish independence, and if the Poles felt it vital to resist such action by force, Britain would come to their aid".Hitler was furious since that meant that the British were committed to political interests in Europe and that Hitler's land grabs such as the takeover of Czechoslovakia would not be taken lightly anymore.Hitler's response to the political checkmate would later be heard at a rally in Wilhelmshaven