 For Germany, because an autarkic economic approach or an alliance with Britain were impossible, closer relations with the Soviet Union to obtain raw materials became necessary but not only for economic reasons.An expected British blockade in the event of war would also create massive shortages for Germany in a number of key raw materials.After the Munich agreement, the resulting increase in German military supply needs and Soviet demands for military machinery, talks between the two countries occurred from late 1938 to March 1939.