We estimate that India may have produced enough military plutonium for 140 to 225 nuclear warheads and might have assembled up to 190. After more than a decade of delays, India’s new 500-MWt Prototype Fast Breeder Reactor (PFBR) at the Indira Gandhi Center for Atomic Research near Kalpakkam reached first criticality in April 2026. Fuelled by a stockpile of reactor-grade plutonium separated from India’s first-generation power reactors, the new reactor irradiates a “blanket” of uranium or thorium to produce Plutonium-239 and Uranium-233. If operated at 80% efficiency, the PFBR could hypothetically produce an estimated 140 kg of plutonium-239 per year, sufficient for up to 35 nuclear warheads,” the article said elaborating on India’s nuclear programme.“Several more fast breeder reactors are planned, including two that are in pre-planning stage (FBR-1 and FBR-2) and will be located adjacent to the Prototype Fast Breeder Reactor at Kalpakkam. As compared to India’s estimated 170 nuclear warheads, Pakistan has an estimated stockpile of approximately 170 nuclear warheads, according to a recent SIPRI report.
