Nuclear Regulation Authority Chairman Shunichi Tanaka said Tuesday that establishing a climate that values safety is essential before the nation returns to nuclear power, in light of the Fukushima No. 1 atomic plant disaster that started in 2011.

"It is said that there has been a problem in the mindset of people involved in nuclear power. The biggest prerequisite for our country to use nuclear power is to dispel the trend of downplaying safety," Tanaka told an international conference on nuclear safety marking the 50th anniversary of Japan's entry to the Organization for Economic Cooperation and Development.

Noting that embracing a safety culture is about "doubting, questioning and learning from lessons," the chairman called on participants to understand that nuclear safety cannot be ensured unless continuing efforts are made to improve safety.

"I hope (this conference will lead) to international affirmation that satisfying regulations is the minimum condition to ensure safety," he added.

The remarks were made as the NRA is moving closer to finishing safety inspections of a nuclear power plant in Kagoshima Prefecture. The plant will likely become the first to clear the country's new nuclear regulations introduced because of the Fukushima crisis.

The government has said it will push for the restart of reactors that clear the new requirements, indicating the nation may eventually see all 48 of its idled commercial reactors online.