SANTIAGO, Chile (AP) — Defense Secretary Jim Mattis says his senior military assistant, Navy Vice Adm. Craig Faller, will be nominated to serve as the next head of U.S. Southern Command.

Mattis made the statement to members of a Chilean government delegation before attending a signing ceremony for an agreement on cyber cooperation with Chilean Defense Minister Alberto Espina.

The nomination was expected to be publicly announced later Thursday in Washington.

Faller would need to be confirmed by the Senate. He would succeed Navy Adm. Kurt Tidd.