New START Expires: US and Russia Enter Unchecked Nuclear Arms Race

The New START nuclear arms control treaty expired at midnight on Thursday, February 5, 2026 — marking the end of an era. UN Secretary-General António Guterres urgently called on the United States and Russia to immediately resume negotiations for a successor agreement, warning that the risk of nuclear weapon use is now at its highest level in decades. With the two nations holding roughly 80% of the world’s nuclear warheads, the lapse leaves global strategic stability severely undermined. New START, signed in 2010, capped each side at 800 deployed delivery systems and 1,550 deployed warheads, while mandating data exchanges and verification inspections — all suspended since 2023 due to the war in Ukraine. This is the first time in over 50 years with no binding limits on US or Russian strategic nuclear arsenals. The US withdrew from the INF Treaty in 2019, another cornerstone arms control pact. Guterres emphasized that arms control agreements since the Cold War have prevented catastrophe, built stability, and enabled massive reductions in nuclear stockpiles. He urged both powers to translate words into action — returning to negotiations without delay to establish a verifiable, risk-reducing successor framework.