He was elected to the Norwegian Parliament from Akershus in 1981, and was re-elected on six occasions. He had previously served as a deputy representative during the term 1973–1977. From 2001 to 2005, when the second cabinet Bondevik held office, Petersen was Minister of Foreign Affairs. During this period his seat in parliament was taken by André Oktay Dahl.
On the local level Petersen was a member of Oppegård municipal council from 1967 to 1983, serving as mayor from 1975 to 1981.
He chaired the Conservative Party from 1994 to 2004. From 1971 to 1973 he was the leader of the Young Conservatives (Unge Høyre), the youth wing of the Conservative Party.
Outside of politics, Petersen has a cand.jur. degree from the University of Oslo in 1973. Before entering national politics he worked for a few years in the Norwegian Agency for Development Cooperation (Norad).
NORWAY: FOREIGN MINISTER THINKS POLAND'S YES WILL BOOST SUPPORT FOR NORWEGIAN MEMBERSHIP.(Jan Petersen on European Union membership)(Brief Article)
Jun 11, 2003; Foreign Minister Jan Petersen (Con) believes that the referenda on EU membership being held in Poland and other eastern European...
NORWAY: GOVERNMENT DIVIDED OVER US MILITARY COURTS.(Prime Minister Kjell Magne Bondevik and Foreign Minister Jan Petersen have differing views)(Brief Article)
Jan 08, 2002; The Bondevik government is divided in its reaction to the USA's new military tribunals. Prime Minister Kjell Magne Bondevik has...