U.S. Defense Secretary Jim Mattis is pledging closer defense cooperation with Argentina.

Standing beside his Argentinian counterpart, Oscar Aguad, Mattis said the military partnership can be strengthened. He alluded to the help the U.S. Navy provided Argentina last November when one of its submarines went missing with 44 sailors aboard.

Mattis's visit is the first to Argentina by an American secretary of defense since Donald H. Rumsfeld in 2005.

U.S. Secretary of Defense Jim Mattis talks during a press conference at the Defense Minstry in Buenos Aires, Argentina Wednesday, Aug. 15, 2018. Mattis is on a official visit to several South American countries, including Brazil, Argentina, Chile and Colombia. (AP PhotoNatacha Pisarenko)

U.S. Secretary of Defense Jim Mattis talks during a press conference at the Defense Minstry in Buenos Aires, Argentina Wednesday, Aug. 15, 2018. Mattis is on a official visit to several South American countries, including Brazil, Argentina, Chile and Colombia. (AP PhotoNatacha Pisarenko)

Mattis also is visiting Chile and Colombia this week.

U.S. Secretary of Defense Jim Mattis, left, and Argentina's Defense Minister Oscar Raul Aguad arrive for a press conference in Buenos Aires, Argentina Wednesday, Aug. 15, 2018. Mattis is on an official visit to several South American countries. (AP PhotoNatacha Pisarenko)

U.S. Secretary of Defense Jim Mattis, left, and Argentina's Defense Minister Oscar Raul Aguad arrive for a press conference in Buenos Aires, Argentina Wednesday, Aug. 15, 2018. Mattis is on an official visit to several South American countries. (AP PhotoNatacha Pisarenko)