US President-elect Joe Biden named retired army general Lloyd Austin to be secretary of defence on Tuesday, who if confirmed will become the first African-American to lead the Pentagon. "Throughout his lifetime of dedicated service -- and in the many hours we've spent together in the White House Situation Room and with our troops overseas -- General Austin has demonstrated exemplary leadership, character, and command," Biden said in a statement. "He is uniquely qualified to take on the challenges and crises we face in the current moment." pmh/