Quisling and his assistant, Hagelin, went to Berlin on
December 14, and were taken by Raeder to Hitler, to discuss a political stroke in Norway. Quisling arrived with a detailed plan. Hitler, careful of secrecy, affected reluctance to increase his commitments, and said he would prefer a neutral Scandinavia. Nevertheless, according to Raeder, it was on this very day that he gave the order to the Supreme Command to prepare for a Norwegian Operation.
Winston S. Churchill, The Gathering Storm