By Fredrik Dahl
VIENNA (Reuters) - The United States and Russia have helped ship out nearly 16 kilograms (35 pounds) of highly enriched uranium from Vietnam as part of a global campaign to reduce the use of nuclear fuel that could also provide material for bombs.
The move - making Vietnam the 11th country from which all highly enriched uranium has been removed in the last four years - was announced during a meeting in Vienna on how to prevent potential bomb ingredients from falling into the wrong hands.
There are about 1,440 tonnes (1 tonne = 1.102 tons) of highly enriched uranium (HEU) and 500 tonnes of plutonium stockpiled and in nuclear arms globally, says the Nuclear Security Governance Experts Group (NSGEG) lobby group. Most of it is under military guard but some for civilian uses is less stringently secured.
Analysts say that radical groups could theoretically build a crude but deadly nuclear weapon if they had the money, technical knowledge and materials needed.
"With this accomplishment (in Vietnam), we will have removed nearly all highly enriched uranium from Southeast Asia," U.S. Energy Secretary Ernest Moniz said. The material, he said, will be downblended into low-enriched uranium to fuel power reactors.
But, "highly enriched uranium still exists in too many places where there are viable alternatives," said Moniz.
Refined uranium fuels nuclear energy reactors but, if processed further, can also form the fissile core of nuclear bombs. Highly-enriched uranium has traditionally been used for research reactors, making such plants especially sensitive.
The first uranium shipment from Vietnam's Dalat Nuclear Research Institute to Russia, where it originally came from, took place six years ago and there was a second delivery this month, Russian envoy Grigory Berdennikov said.
The U.N. nuclear agency and Canada also provided assistance.
In the previous such case, the White House said in April that the United States and its allies secured 68 kilograms (150 pounds) of highly enriched uranium from the Czech Republic.
JAPAN'S PLUTONIUM PLANS
Obtaining weapons-grade fissile material poses the biggest challenge for militant groups, so it must be kept secure both at civilian and military facilities, experts say.
A fairly simple-to-design bomb would require about 50-60 kg of highly enriched uranium, the NSGEG said. More sophisticated devices would need less material, experts say.
The United States is working with other countries to "implement technologies to minimize and eventually eliminate the civilian use" of HEU, Moniz said.
He also said he had asked Japanese officials during the week-long nuclear security conference in Vienna "of how the planning is going to manage plutonium stocks" in the country.
But Japan's plans for a major nuclear fuel reprocessing facility - which would yield plutonium for the recycling of spent reactor fuel - is "clearly a sovereign choice in terms of how Japan operates its fuel cycle", he said.
In May, the Wall Street Journal said Japan was preparing to start up the Rokkasho facility over the objections of the U.S. administration, which it said fears the move may stoke a broader race for nuclear technologies and even weapons in North Asia and the Middle East. Japanese officials have said the plutonium would strictly be used for power generation, the WSJ added.
(This story was published again to correct a spelling error in paragraph 8, and to add the name of group in paragraph 12)
(Editing by Mark Heinrich)