The doubts about the French willingness to undertake an offensive against Germany were further reinforced by the Remilitarization of the Rhineland in March 1936 which had the effect of allowing the Germans to start building the Siegfried line along the border with France, something that considerably lessened the prospect of a French offensive into western Germany if the "Reich" should invade any of the states of the "cordon sanitaire". A British Foreign Office memo from March 1936 stated that only nations in the world that would apply sanctions on Germany for remilitarizing the Rhineland if the League of Nations should vote for such a step were Britain, France, Belgium, Czechoslovakia, the Soviet Union and Romania. In the aftermath of the remilitarization of the Rhineland and once it was clear that no sanctions were going to be applied against Germany, Carol started to voice his fears that the days of French influence in Eastern Europe were numbered and Romania might have to seek some understanding with Germany to preserve its independence. With continuing the alliance with France, after March 1936 Carol also began a policy of attempting to improve relations with Germany.