 Complete the following phrase:  The United States and Sudan entered an agreement in November 1976 to provide Sudan with selected arms. The United States sold Sudan transport aircraft ficed by Saudi Arabia, followed several years later by F-5 combat airplanes. Believing that Sudan was threatened by neighboring Ethiopian and Libyan forces heavily armed by the Soviet Union, Washington adopted a growing role in Sudans security. Between fiscal year 1979 and 1982, military sales credits rose from 5 million to 100 million. Subsequent aid was extended on a grant basis. United States aid consisted of M113 APCs, M60A1 tanks, artillery, and Commando armored cars. United States grant aid reached a peak of 101 million in 1982; at the time, this constituted two-thirds of all United States military assistance to sub-Saharan Africa. Sudan granted the United States naval port facilities at Port Sudan and agreed to some prepositioning rights for military equipment for contingent use by the United States Central Command. Sudanese and United States forces participated in Operation Bright Star in 1981 and 1983. When 