These figures include retired warheads which are set to be dismantled.
At the same time, the report says the number of deployable weapons increased from 3,720 to 3,825 over the previous year.
“The overall number of warheads in global military stockpiles now appears to be increasing, a worrisome sign that the declining trend that has characterized global nuclear arsenals since the end of the Cold War has stalled,” SIPRI researcher Hans M.
The US and Russia have been dismantling retired warheads.
China, India and Pakistan are three other countries that are rapidly modernizing and boosting their arsenals.