China is developing advanced fast reactors and reprocessing facilities as it seeks to reduce dependency on coal, which emits emissions harmful to human health and that worsen climate change. But reprocessing also produces plutonium that could be used to make nuclear weapons.

China's push to develop fuel for a new generation of nuclear power reactors will produce large amounts of materials that could be diverted to making nuclear weapons, non-proliferation experts said on Thursday.

China is developing advanced fast reactors and reprocessing facilities as it seeks to reduce dependency on coal, which emits emissions harmful to human health and that worsen climate change. But reprocessing also produces plutonium that could be used to make nuclear weapons.

There is no evidence that China intents to divert its potential plutonium stockpile to weapons use, but concern has grown as Beijing is expected to boost its number of nuclear warheads over the next decade from the low 200s now.

"To reduce international concerns about the potential plutonium diversion issues, China needs to keep its plutonium recycling programs more transparent including timely reporting of its stockpile of civilian plutonium like they did before 2016," Hui Zhang, a senior research associate at Harvard University's Project on Managing the Atom, said in an email.

Zhang, a contributor to a Non-proliferation Policy Education Centre report called "China's Civil Nuclear Sector: Plowshares to Swords?", said China should also offer to have its plutonium recycling facilities monitored by the U.N.'s International Atomic Energy Agency.

China's embassy in Washington did not immediately respond to a request for comment.

The report recommended that Washington urge China to join the United States, South Korea and Japan, in sharing information on current plutonium and enriched uranium holdings and production capacities.

It also recommended that Washington explore with those countries, the possibility of taking a plutonium production timeout. Japan, South Korea, and the United States should offer to delay their plutonium production and fast reactor programs, if China does likewise, it said.

Leaders from those countries should work to "forestall industrial scale reprocessing, which would only make the entire region, and the world, less secure," Christopher Ford, a non-proliferation official under Donald Trump, and Thomas Countryman, who served the same role under Barack Obama, said in the report's preface.

The U.S. Departments of State and Energy did not immediately respond to a request for comment.