North Korea reportedly has the capability to produce more uranium for nuclear weapons than previously known. 

According to The Wall Street Journal on Thursday, the Center for International Security and Cooperation at Stanford University in the U.S. reached the conclusion after analyzing satellite images of the Pyongsan uranium mining facility in North Korea from 2017 to 2020.

The center reportedly conducted the analysis with artificial intelligence and tracking changes in deforestation and land use to study North Korea’s uranium mining activities.

The researchers said in the report that North Korea’s annual uranium mine production was previously estimated at 30-thousand metric tons, but its maximum mining capacity could reach 360-thousand metric tons a year.

The Journal said these estimates suggest that North Korea has the ability to process uranium concentrates to obtain up to 340 kilograms of highly enriched uranium per year and that's enough to make more than 20 nuclear bombs annually.