The United States would back a change to Japan's nuclear fuel reprocessing program because there are concerns it may lead to an increase in its ally's stockpile of unused plutonium, a senior White House official said.
If Japan were to change course "they would find the United States to be supportive," Jon Wolfsthal, senior director for arms control and nonproliferation at the National Security Council, said in a recent interview.
Wolfsthal's remark reflected concerns in President Barack Obama's administration about the future of Japan's large plutonium stockpiles, which can be used to make nuclear weapons.