From August 15, 2001, to February 28, 2005, Coats was the United States Ambassador to Germany. As ambassador during the lead-up to the Iraq war, he pressured the German government not to oppose the war, threatening worsened US relations with Germany. As Ambassador he also played a critical role in establishing robust relations with then opposition leader Angela Merkel and in the construction of a new United States Embassy in the heart of Berlin next to the Brandenburg Gate.