By 1985, international isolation and economic hardships had forced Vietnam to rely more and more on the Soviet Union for help. During the Chinese invasion in February 1979, the Soviet Union provided US$1.4 billion worth of military aid to Vietnam, a figure that peaked at US$1.7 billion in the period between 1981 and 1985. Then, to help Vietnam implement its third Five Year Plan (1981–1985), the Soviet Union provided a sum of US$5.4 billion to the Vietnamese Government for its expenditures; economic aid ultimately reached US$1.8 billion annually. The Soviet Union also provided 90% of Vietnam's demand for raw materials and 70% of its grain imports. Even though the figures suggest the Soviet Union was a reliable ally, privately Soviet leaders were dissatisfied with Hanoi's handling of the stalemate in Kampuchea and resented the burden of their aid program to Vietnam as their own country was undergoing economic reforms. In 1986, the Soviet Government announced that it would reduce aid to friendly nations; for Vietnam, those reductions meant the loss of 20% of its economic aid and one-third of its military aid.