 On October 11, 1949, United States Secretary of State Dean Acheson appointed Gross as the United States' deputy delegate to the United Nations.Only two months later, the chief delegate, Warren Austin, took a leave of absence, and Gross took over as acting head of the U.S. delegation to the U.N.The major issue facing the United Nations at that time was the Soviet Union's proposal that, with the conclusion of the Chinese Civil War, the Communist People's Republic of China should replace the Republic of China on the United Nations Security Council.