News World. Only 10 countries in the world possess nuclear weapons, with Russia and the United States holding over 90% of the global nuclear arsenal. Here’s a breakdown of each country’s stockpile: 1. Russia - Total warheads: 5,449 - Program start: 1949 - Key fact: Russia has the largest nuclear missile stockpile in the world. 2. United States - Total warheads: 5,277 - Program start: 1945 (first nuclear test) - Key fact: The only country to have used nuclear weapons in war (Hiroshima & Nagasaki). 3. China - Total warheads: 600+ - Program start: 1964 - Key fact: The third-largest nuclear power and Nepal’s neighbor. 4. France - Total warheads: 290 - Program start: 1960 - Key fact: The sole nuclear-armed EU nation. 5. United Kingdom - Total warheads: 225 - Program start: 1952 - Key fact: Maintains a sea-based deterrent (Trident missiles). 6. India - Total warheads: 18...