As an elected politician he served as a deputy representative to the Parliament of Norway from Oslo during the term 1965–1969. He chaired Oslo's city chapter of the Labour Party from 1969 to 1972, and was a member of the central committee of the Labour Party from 1972 to 1981. During Trygve Bratteli's First and Second Cabinet, from 1972 to 1972 and 1973 to 1976, Gjerde was appointed as Minister of Education and Church Affairs. In Nordli's Cabinet he was given the Minister of Industry post, which he held until 11 January 1978 when he left to become the first Minister of Petroleum and Energy in Norway. He held the latter position until October 1980, when Arvid Johanson replaced him. His time was marked by several extraordinary incidents, including the Alta controversy and the Alexander Kielland rig disaster.
