Former Foreign Minister of the GDR, pastor. He serves as Chairman of the Federal Council of the Foundation for Research into the SED Dictatorship, whose establishment he initiated. He is also a member of the board of trustees of the European Network Remembrance and Solidarity. From 12 October 2013 to 22 September 2016 he served as President of the German War Graves Commission. He works on European foreign policy and advocates for the support of democracy.

He studied theology in Naumburg and Berlin. From the 1970s he was involved in political opposition activities in the former GDR. In 1989 he co-founded, with Martin Gutzeit, the Social Democratic Party (SDP) in the GDR. In 1990 he served as acting chairman of the eastern SPD. After the free elections in 1990 he was a member of the GDR People’s Chamber and Foreign Minister of the GDR.

Member of the Bundestag from 1990 to 2009, and Chairman of the German-Polish Parliamentary Group from 1994 to 2009. He served as Deputy Foreign Policy Spokesperson of the SPD parliamentary group. From 1998 to 2006 he was Chairman of the German Delegation to the NATO Parliamentary Assembly, and from 2000 to 2002 Vice-President of the NATO Parliamentary Assembly.