Key Findings 

• Global Nuclear Stockpile Decline: Since the end of the Cold War, the number of retired warheads has exceeded new deployments. 
• Countries Expanding Stockpile: China is expanding fastest, with its stockpile now at least 600 warheads.
  • India’s arsenal increased from 172 to 180 warheads, more than Pakistan's (170). 
• Modernisation: In 2024, all 9 nuclear-armed countries continued to modernise their arsenals.
• Status of Fissile Materials: The explosive material utilized in nuclear weapons is fissile material, either highly enriched uranium (HEU) or separated plutonium. 
  • China, and Pakistan have produced both HEU and plutonium for use in their nuclear weapons. 
  • India and Israel have produced mainly plutonium.
• Emerging Threats: 
  • Modern Technologies: The rapid development of artificial intelligence (AI), cyber capabilities, space assets, missile defence and quantum are radically creating potential sources of instability. 
• Arms control in crisis: While New START remains in force until early 2026, there are no signs of negotiations to renew or replace it.