A Stockholm-based think tank estimates that North Korea has assembled up to 20 nuclear warheads, amid widespread expectation that Pyongyang will soon conduct a seventh nuclear test.

The Stockholm International Peace Research Institute (SIPRI) said in its 2022 annual yearbook released Monday (local time) that North Korea likely possesses enough fissile material to assemble around 45 to 55 nuclear devices as of Jan. 2022.