World Leaders Urge Action against Nuke Terrorism

World leaders called Tuesday for strong action to combat the threat of nuclear terrorism, including minimizing civilian use of highly enriched uranium (HEU), which can be turned into bombs.

"Nuclear terrorism continues to be one of the most challenging threats to international security," said a joint communique at the end of a two-day summit in South Korea bringing together leaders or top officials from 53 nations.

"Defeating this threat requires strong national measures and international cooperation."

The leaders, including U.S. President Barack Obama and Chinese President Hu Jintao, stressed the "fundamental responsibility" of all nations to safeguard nuclear material and keep it out of the hands of terrorists.

It also urged all countries to accede to international conventions on protecting fissile material, and reaffirmed the central role of the U.N.'s atomic watchdog, the International Atomic Energy Agency.

One of the key points in the communique was an emphasis on the need to secure stocks of HEU, which is used to make weapons but also in nuclear power plants and medical devices.

The communique called for nations to minimize the use of HEU, with nations encouraged to announce by the end of 2013 how they would do so.

This could include the conversion of reactors from HEU to low-enriched uranium fuel which cannot be weaponized.

The communique called for effective inventories and tracking mechanisms for nuclear material and the development of forensics capacities to determine its source.

The leaders also welcomed "substantive progress" on national commitments made at the first nuclear security summit in Washington in 2010.

This included the disposal of 480 kilograms of HEU -- enough to make about 19 nuclear weapons -- from eight countries.

Ukraine and Mexico have cleaned out all stockpiles of HEU, while Russia and the United States have converted HEU equivalent to 3,000 nuclear weapons down to low-enriched uranium.

Experts said modest progress had been made in Seoul but cautioned many of the tough issues to fully solve the problem had not been addressed, with countries unwilling to make binding and transparent agreements.

"The current nuclear material security regime is a patchwork of unaccountable voluntary arrangements that are inconsistent across borders," said Ken Luongo, co-chair of the Fissile Materials Working Group, a group of non-proliferation experts.

"Consistent standards, transparency to promote international confidence, and national accountability are additions to the regime that are urgently needed."

The final communique also omitted a reference to the need for "concrete steps" towards a world without nuclear weapons, a phrase which had been included in a draft statement dated March 21 and seen by Agence France Presse.

The leaders said merely that they "reaffirm our shared goals of nuclear disarmament, nuclear proliferation and peaceful uses of nuclear energy".

A Seoul government official told AFP on condition of anonymity that some nations had been uncomfortable about expanding the scope of the summit into nuclear weapons reduction and disarmament, and the call for concrete steps.