WASHINGTON (Reuters) - Representative Buck McKeon, who heads the House Armed Services Committee, on Monday blasted the Pentagon's proposed defense budget for fiscal 2013, saying it "irresponsibly ignores" additional mandatory cuts that are due to take effect in January 2013.

"This budget reflects a true reduction, in real terms, of military spending while we have troops in combat," McKeon said in a statement responding to a Pentagon request for a base budget of $525 billion in 2013, about $5.1 billion less than approved in 2012.

"It irresponsibly ignores the looming threat of sequestration, while failing to adequately address threats posed by our adversaries around the world," McKeon said. Sequestration refers to automatic spending cuts.

(Reporting By Andrea Shalal-Esa; Editing by Jackie Frank)