Between 1955 and 1961 Rau served as Minister for Foreign Trade and Inter-German Trade. The term "Inter-German Trade" meant the trade with West Germany. In this time both German states still saw German reunification as their own aim, but both envisaging different political systems. The West German position was that they, as the only freely elected government, had an exclusive mandate for the entire German people. In consequence of this, the GDR's official diplomatic relationships with other states were narrowed to the states of the Eastern Bloc. Practically no other states recognized the GDR. As a result, Rau's ministry established numerous new "trade missions" in other states, which served as a kind of surrogate for nonexistent embassies. It was a corollary, that Rau, in addition to his responsibility for the export-oriented industry, also chaired the Foreign Policy Commission of the SED Politburo ("Außenpolitische Kommission beim Politbüro" or "APK") since 1955, in this period the actual decision-making body for foreign affairs, and visited other states in different parts of the world in this capacity. Among the visited states were, beside the core states of the Soviet Bloc, also then Eastern Bloc peripheral states, like China and Albania and leading states of the crystallizing Non-Aligned Movement like India and Yugoslavia (after the Bandung Conference). Between 1955 and 1957 he visited, as part of a diplomatic advertisement campaign in the Arab world, various Arabic states, among them repeatedly Egypt. One of his last deals, which he closed as minister, was a trade agreement with Cuba, signed by Cuba's minister Ernesto 'Che' Guevara, on 17 December 1960 in East Berlin.