Mr Tesch was appointed Deputy Secretary on 1 May 2019 and heads the Strategy, Policy, and Industry Group at the Australian Department of Defence. 

Mr Tesch comes to this role following a distinguished career as a senior officer with the Department of Foreign Affairs and Trade (DFAT). He most recently served as Australia’s Ambassador to the Russian Federation from March 2016 until April 2019. Prior to this, he held several executive positions in DFAT, including as First Assistant Secretary International Security Division from January 2014 to December 2015. Mr Tesch has also previously served in the Office of the Minister for Trade (1993-1994).

He has previously represented Australia overseas as Ambassador to Germany (2009-2013); Commissioner-General for the Shanghai 2010 World Expo (2008-2009); Deputy Permanent Representative to the United Nations, New York (2002-2005); Deputy Commissioner-General at the Expo 2000, Hanover (1999-2000); Ambassador to Kazakhstan (1997-1999); and Third Secretary, Moscow (1989-1991).

Mr Tesch holds a Bachelor of Arts degree with Honours from the University of Queensland. He speaks German and Russian.