The recent power plant accident in Japan, like the Chernobyl disaster 25 years ago, calls for "deep reflection" on the future of nuclear energy, Secretary-General Ban Ki-moon said today, as he outlined a five-step plan to enhance nuclear safety.

"As we are painfully learning once again, nuclear accidents respect no borders," Mr. Ban told the Summit on the Safe and Innovative Use of Nuclear Energy, held in Kiev, Ukraine.

"They pose direct threats to human health and the environment. They cause economic disruptions, affecting everything from agricultural production to trade and global services."

Mr. Ban said that both the explosion at the Chernobyl nuclear power plant in Ukraine in 1986 and the accident at Japan's Fukushima Daiichi plant last month raise popular fears and disturbing questions, while offering lessons for the global community.

"This is a moment for deep reflection: How do we ensure both the peaceful uses of nuclear energy and maximum safety? We need a global rethink on this fundamental question," he said.

"Because the consequences are catastrophic, safety must be paramount," said the Secretary-General. "Because the consequences are transnational, they must be debated globally."

Enhancing nuclear safety must begin with "a top to bottom review" of current nuclear safety standards, both at the national and international levels, he stated.

Noting that the primary responsibility for ensuring the safety of nuclear installations lies with national governments, he strongly urged States to consider lessons learned and adopt appropriate measures to apply the highest possible safety standards.

Second, he cited the need to strengthen support for the UN International Atomic Energy Agency (IAEA) on the challenge of nuclear safety, saying the time has come to boost the body's capacity in the further development and universal application of the highest possible nuclear safety standards.

"Third, we must put a sharper focus on the new nexus between natural disasters and nuclear safety," he stated. "The challenge of climate change is bringing with it greater extremes of weather. Nuclear power plants must be prepared to withstand everything from earthquakes to tsunamis, from fires to floods."

According to the IAEA, 64 new reactors are under construction. Today, 443 are operating in 29 countries worldwide, some located in areas of seismic activity.

"This requires us to place new importance on disaster preparedness, in rich and poor nations alike," Mr. Ban said.