In 1985, President Paul Biya recalled Oyono from London and appointed him as Secretary-General of the Presidency of Cameroon. Oyono remained in the post for about a year before Biya instead appointed him as Minister of Town Planning and Housing in 1986. The post of Secretary-General of the Presidency was historically very powerful, but Oyono's stint in the office was associated with a weakening of it under President Biya; significantly, Oyono was moved from the Secretariat-General to an ordinary ministry—effectively a demotion. Although Oyono was dismissed from the government in 1990, he was subsequently appointed as Minister of Foreign Relations on 27 November 1992, serving in that position until he was instead named Minister of State for Culture on 8 December 1997. Oyono was a member of the National Commission for the co-ordination of President Biya's re-election campaign in the October 2004 presidential election and was the president of the campaign's support and follow-up committee in the South Province.