Japan has agreed to send the United States 730 pounds of plutonium, yielding to a years-old demand by the Obama administration, Kyodo News reports.
Tokyo previously sought to avoid turning over the U.S.-origin material, Japanese and U.S. officials told the news agency on Sunday. The government personnel added that Washington is still pursuing an agreement with London to permit U.S. custody of a portion of the plutonium manufactured in the United Kingdom.
The material reportedly is capable of fueling between 40 and 50 nuclear bombs, and one Japanese analyst said the science-grade substance is better suited for use in arms than the rest of the island nation's 44-ton stockpile.
The United States anticipates inking a transfer arrangement with Japan at the third Nuclear Security Summit, scheduled for March in the Netherlands. The sides have been in talks on the matter since 2013. The government insiders said, though, that U.S. officials have pressed Japan to relinquish the material since the first nuclear summit took place in 2010.
In making their case for keeping the plutonium in Japan, scientists and the nation's education ministry contended that the substance plays an irreplaceable role in domestic nuclear experiments. The United States provided the plutonium during the Cold War, for the Japan Atomic Energy Agency's Fast Critical Assembly. That site is the island nation's sole facility for examining the behavior of neutrons in fast reactors.
The United States for years has sought to consolidate and do away with bomb-usable atomic materials around the world. The effort is intended to lower the likelihood of extremists obtaining potential fuel for a nuclear weapon.