Bulgaria's foreign policy under Zhivkov, however, continued on an even, strongly Soviet, keel. Bulgaria's foreign policy has been assessed by some observers as "a carbon copy of Moscow's." Bulgaria was, and is, considered to be the most reliable partner of the Soviet Union in the Balkans. In contrast, Albania has supported the PRC, Romania has pressed its case for independence, and Yugoslavia has essentially followed a nationalistic policy. Bulgaria's relations with Greece, which had been basically negative for twenty years, became more positive in 1964 when trade, air traffic, communications, and tourist agreements were signed. Because of the issue of Macedonia, relations with Yugoslavia were, for the most part, cool, although Zhivkov attempted to improve them from time to time. Relations with the United States remained cool but correct. In 1965, shortly after Khrushchev's ouster in the Soviet Union, there was an attempted coup against Zhivkov. The government tried in vain to silence the story but, when pressed, stated that the conspirators in the plot were Maoists, alienated by Bulgaria's anti-PRC policies. As the coup was attempted only five months after Khrushchev's removal from office, Zhivkov--whose power had been based to a large extent on Khrushchev's support--was in a highly vulnerable position. For this reason many attributed the conspiracy to those opposed to Zhivkov's government itself and particularly those opposed to its subservience to the Soviet Union. The conspirators included Bulgarian Communists, army officers, and World War II partisans. The discovery of this plot resulted in purges, the suicide of one of the leading conspirators, and the reorganization of the Ministry of the Interior and the transfer of its security functions to the new Committee of State Security, which fell directly under Zhivkov's personal control. CHAPTER 3 PHYSICAL ENVIRONMENT AND POPULATION Bulgaria occupies 42,800 square miles of the Balkan Peninsula, and its 1973 population was estimated at 8.7 million (see fig. 1). It is a member of the Warsaw Treaty Organization (Warsaw Pact), together with five other Eastern European countries to its north and northwest and the Soviet Union. Bulgaria's location is such that its natural features are combinations of those found in the western Soviet Union and in southern Europe. Its climate is transitional between that of the Mediterranean countries and that of north-central Europe. The blend of the various geographic influences is unique, however, and gives the country a degree of individuality that is not anticipated until it is explored in some detail.