Nearly 90 countries including the world's largest nuclear powers agreed on Friday to close loopholes in an international pact on the protection of atomic materials against terrorists and saboteurs. The United Nations nuclear watchdog said 89 countries at a conference in Vienna adopted changes to a 1979 treaty that will require states to boost security at nuclear sites and co-operate more to track down stolen or smuggled atomic materials.
A key change extends the convention's existing rules for securing international shipments to cover nuclear materials being shipped or stored within a country, the International Atomic Energy Agency (IAEA) said in a statement.
"This new and stronger treaty is an important step towards greater nuclear security by combating, preventing, and ultimately punishing those who would engage in nuclear theft, sabotage or even terrorism," IAEA head Mohamed ElBaradei said.
The changes to the 1979 Convention on the Physical Protection of Nuclear Material (CPPNM) were proposed by the United States, Canada, Australia, Japan and 20 European states and backed by Russia and China.
According to the IAEA's website, among the countries not party to the CPPNM are Iran, Georgia and Kazakhstan - all states that at some time represented significant nuclear security threats, according to non-proliferation analysts.
The amendments require signatories to protect nuclear material by adopting proper legislation, ensuring that a competent regulatory body is chosen and taking any other appropriate measures.
The IAEA said the new rules will come into effect once they have been ratified by two-thirds of the 112 states that are parties to the original convention, a process that is expected to take several years.