"Their administration spoke," he told reporters. "The president takes responsibility not just for the words that come from his mouth but also the words that come from his ambassadors, from his administration, from his embassies, from his state department. They clearly sent mixed messages to the world and the statement... is akin to an apology."
Obama, appearing with Secretary of State Hillary Clinton in the Rose Garden after Romney finished his press conference in Florida, made no mention of his rival but said "There is absolutely no justification for this type of senseless violence, none," and vowed to "bring justice to the killers."
Vice President Joe Biden was similarly circumspect with his comments.
"There is no place in the civilized world for senseless murder like what occurred last night, " he said at a rally in Ohio. "Our ambassador was in Benghazi while the war was going on, our ambassador risked his life repeatedly while war in Libya to get rid of that dictator was going on."
Republican vice presidential candidate Rep. Paul Ryan, who spoke in De Pere, Wisc., was also less overtly political than Romney.
"In the face of such a tragedy, we are reminded that the world needs American leadership," Ryan said, managing a quick dig at the president. "And the best guarantee of peace is American strength."