Ms. Tetteh is the Special Representative of the Secretary-General and Head of the UN Mission in Libya (UNSMIL). Prior to that she held a number of senior positions in the UN as follows: (2022-2024) UN Special Envoy for the Horn of Africa; (2019-2022) Special Representative of the Secretary-General and Head of the UN Office to the African Union; and (2018) Director General of the United Nations Office in Nairobi. Ms. Tetteh has decades of experience in international relations, foreign policy and governance at the national, regional and international levels.

Ms. Tetteh served in Government in the Republic of Ghana as a Cabinet Minister and as a Member of Parliament. She was Minister for Foreign Affairs and Regional Integration (January 2013-January 2017), and in this position was also a member of the National Security Council and the Armed Forces Council. During her tenure as Foreign Minister between 2014 to 2015, she was also the Chairperson of the Council of Ministers and of the Mediation & Security Council of ECOWAS (the Economic Community of West African States) at the time when Ghana was chairing the organization.

Ms. Tetteh served as Minister for Trade and Industry (February 2009 to January 2013) and in this position was Chairperson of the Ghana Free Zones Board, Member of the National Development Planning Commission and Member of the Board - Millennium Development Authority. She served two terms as a Member of Parliament, representing the Awutu Senya West Constituency.

Ms. Tetteh was previously involved in high-level mediation activities when she was appointed Co-Facilitator of the Forum for the Revitalisation of the Agreement for the resolution of the conflict in South Sudan (2017-2018). She qualified as a Barrister in 1992 and holds a Bachelor of Laws (LLB) degree from the University of Ghana, Legon (1989), and completed her post graduate professional legal studies at the Ghana School of Law.