The Nuclear Regulation Authority gave a green light Wednesday to extending the life of Kansai Electric Power Co.'s 40-year-old Mihama No. 3 reactor in Mihama, Fukui Prefecture, by 20 years.

The ruling was certain to provoke questions in Kansai and elsewhere about whether the NRA is lax on safety concerns.

Safety work related to the extension still needs to be carried out and is expected to take years to complete. Kepco hopes to restart the reactor sometime after the summer of 2020.