The government announced a new safety assessment plan for nuclear power plants Monday, making it precondition that reactors undergoing check-ups to pass the first stage of the so-called stress test before restarting them.

With the two-staged tests to push back the resumption of reactors, Japan could face even more serious lack of electricity this summer.

Chief Cabinet Secretary Yukio Edano announced the plan during a news conference Monday, but he gave no specific timeline as to when the tests would actually start and for how long it would last.