The head of Tepco said Wednesday that the company will make a legal safety pledge — in response to a request by the nation's nuclear watchdog — as it seeks approval to restart reactors at its Kashiwazaki-Kariwa plant in Niigata Prefecture.

Tomoaki Kobayakawa, president of Tokyo Electric Power Company Holdings Inc., told the Nuclear Regulation Authority that the firm will work to build a culture of safety as it seeks the restart of undamaged but idled reactors 6 and 7 at the plant on the Sea of Japan coast.

The nuclear watchdog called for the pledge as part of the firm's legally binding reactor safety program because it operates the Fukushima No. 1 nuclear power plant, the site of a major nuclear disaster in the aftermath of the massive March 2011 earthquake and tsunami.