TOKYO, Nov 21 (Reuters) - Japan's transport minister said on Friday that he had directed Takata Corp to investigate its defective air bags, adding that the ministry was directly in touch with the supplier over the issue.

Japan's transport ministry usually works through automakers in recall matters but in this case was directly in touch with Takata, underscoring the severity of the matter.

Transport Minister Akihiro Ohta also told a news conference that he was asking automakers to determine if it was necessary to widen the recall of air bags to Japan, given the U.S. regulator's order to widen regional recalls nationwide in the United States.

(Reporting by Mari Saito; Editing by Edwina Gibbs and Chris Gallagher)