Environment Minister Yuriko Koike said Tuesday the head of the ministry panel studying the asbestos problem has resigned due to his close ties to the asbestos industry.

Haruhiko Sakurai, professor emeritus of Keio University, served as an adviser to the Japan Asbestos Association, a group comprised of asbestos manufacturers, from 1985 to 1997, and even appeared in a promotional video for the group.

"He contacted me and said he wants to step down as a panel member. It's regrettable, but I plan to accept his resignation," Koike said during a news conference after a Cabinet meeting.