Washington's increasing economic economic embargo led Cuba to seek new markets in a hurry to avert economic disaster. Castro asked for help from the Soviets, and in response, Khrushchev approved the temporary purchase of Cuban sugar in exchange for Soviet fuel. The deal was to play a part in sustaining the Cuban economy for many years to come. After the failed Bay of Pigs Invasion of 1961, Castro announced publicly that Cuba was to become a socialist republic. Khrushchev sent congratulations to Castro for repelling the invasion but privately believed that the Americans would soon bring the weight of their regular army to bear. The defense of Cuba became a matter of prestige for the Soviet Union, and Khrushchev believed that the Americans would block all access to the island by sea or by air.