The Soviet Union's involvement in the Nigerian civil war began in the late summer of 1967. In many ways it was not a propitious time for the USSR to get involved in another local war. The preceding June, Soviet arms had suffered a devastating defeat in the six-day war, and a massive commitment of military aid to the Arabs was required in order to salvage the Soviet Union's prestige and position in the Middle East. Nasser's impending withdrawal from Yemen meant that Moscow would also be forced to increase its military commitment there if the YAR was to be saved. Nigeria's military regime did not appear to offer particularly great promise as a Soviet client, and meeting its weapons requirements would mean the diverting of resources from the priority struggle for influence in the Arab world. The Kremlin went ahead, nonetheless, deterred neither by the prospect of overcommitment nor by sobering memories of its Congo fiasco and other Soviet setbacks in Africa — in Guinea, Ghana, and Mali. Perhaps the Kremlin leaders felt that demonstrations of Soviet largess and capabilities were badly needed and that the Nigerian civil war offered safe and certain victory, given Britain's pro-Federal position, U.S. neutrality, and the Federal army's quantitative superiority over the Biafran forces.