Britain had proposed to lay the great mine barrage across the North Sea from Scotland to Norway . However this could not have been fully effective if the corridor was still open to allow German commerce and U-boat to go through. The Allies urged Norway to close it the corridor themselves. It was not however till the end of the Sep 1918 that the Norwegian Government were persuaded to take action. Before they actually carried out their undertaking the war came to an end.
At the meantime, Russia was attacking Finland and tried to break the Mannerheim line but without much success. Finish fight with spirit and their experience in forest war and their garment for winter had great advantage against massive troop of Red army. The Russian tanks were encountered with audacity and a new type of hand-grenade, soon nicknamed” the Molotov Cocktail”.The hard fight had generated sympathy of most of western countries and had undermined Stalin and Red Army. Maybe Hitler thought: it is pretty easy to conquer Soviet Union and took Russia?