 Complete the following phrase:  North Yemen received its first 64 M60A1s in 1980 as part of a 400 million arms transfer from the United States requested by Saudi Arabia to counter border disputes with the communist Peoples Democratic Republic of Yemen government of South Yemen. During the 1980s Saudi Arabia provided more M60s to North Yemen reaching a height of approximately 250 by 1990. With the collapse of communism, South Yemen was unified with the Yemen Arab Republic commonly known as North Yemen on 22 May 1990, to form the present-day Yemen. After four years, however, South Yemen declared its secession from the north, which resulted in the north occupying south Yemen and the 