It just requires 15-20 kg (vs. ~5 kg Pu). Most of the yield comes from the neutron activation of the U238 casing, so you just need a small fission explosion - any would do. It is bigger than a Pu weapon but it works. Most of the mass and volume of a weapon is in the electronics and conventional explosives, so you'll probably only see a 20-30% increase in size vs a Pu weapon overall. Maybe it'll reduce DF-41 MIRVs from 10x to 6x or something."Concerns grow over China nuclear reactors shrouded in mystery | Nuclear Energy News | Al Jazeera"
The reason these breeder reactors are shrouded in mystery is that China, which had been transparent about its civilian plutonium programme until recently, stopped annual voluntary declarations to the International Atomic Energy Agency [IAEA] on its stocks of civilian plutonium in 2017 and has not added the reactors to the agency’s database to date.
compared to Russia with 28 million and global total of 60 million.