Five years ago West German Chancellor Ludwig Erhard and Foreign Minister Gerhard Schroeder launched a tentative “Opening to the East” which marked a break with Konrad Adenauer's relatively rigid approach to, the Soviet Union and Eastern Europe. The “Grand Conbtion” of the Christian Democrats and Social Democrats continued the experiment from 1966-1969. The Hallstein Doctrine—no diplomatic relations with any country which had such relations with East Germany (the Soviet Union being the sole exception)—was abandoned. West Germany established diplomatic relations with the maverick Rumanian regime, and re-established relations with Tito's Yugoslavia. Several trade and cultural exchange agreements were entered into with East European Communist nations.