These could also promote the creation or extension of a European bloc in Western Europe or in all of Europe, including Eastern Europe, and with some possible participation of the Soviet Union as well. Such a European bloc might be extended to include Africa and the Middle East as well. Similarly, renewed pressures could build up toward the formation of a Japanese "Greater East Asian Co-prosperity Sphere" (to recall the term of the 1930s) in the Pacific area. The possible breakdown of the dollar based international monetary system, which is already manifest in the upgrading of the German mark and Japanese yen, forebodes the possibility also of a creation of economic blocs around the US dollar, the German mark or a mark based Eurocurrency, the Japanese yen, and possibly the Soviet ruble.