He served as Head of the Council of Ministers (equivalent of today's Prime Minister) of the Ukrainian SSR from 1987 until 17 October 1990, when he was forced to resign and was replaced by Vitold Fokin. He was forced into resignation by Ukrainian student protests and hunger strikes known as the "Revolution on Granite". Masol was a member of the Congress of People's Deputies of the Soviet Union between 1989 and 1991.