On June 15, 2021, President Joe Biden nominated Salazar to be the next U.S. Ambassador to Mexico. The Senate Foreign Relations Committee held hearings for his nomination on July 28, 2021. Salazar's nomination was then reported favorably by the committee on August 4, 2021. His nomination was confirmed by the United States Senate on August 11, 2021 by voice vote. He was ceremoniously sworn in by Vice President Kamala Harris on September 2, 2021. On September 14, 2021, Salazar presented his credentials to President Andrés Manuel López Obrador. In July 2022, the New York Times published an article quoting "growing concern within the Biden administration that the ambassador may have actually compromised U.S. interests" and had become too close to sitting Mexican President Andrés Manuel López Obrador.
