New START Nuclear Treaty Expires Amid U.S.-Russia Tensions

The New Strategic Arms Reduction Treaty (New START), the final bilateral agreement limiting the nuclear arsenals of the United States and Russia, formally expired on February 5, 2026. The pact, which capped deployed strategic warheads at 1,550, left both nations without binding limits for the first time since the early 1970s. Donald Trump declined a proposal from Russian President Vladimir Putin to informally extend these limits for one year, characterizing the original 2010 deal as a "badly negotiated deal" that was "grossly violated."

Following the expiration, the Russian government declared that both parties are no longer bound by the treaty's obligations. However, Russian Foreign Minister Sergei Lavrov announced that Moscow would maintain a conditional moratorium on warhead limits as long as the United States does not exceed them. U.S. officials, including Secretary of State Marco Rubio, argue that bilateral treaties are obsolete and that any future "modernized" architecture must include China, whose arsenal is projected to reach 1,000 warheads by 2030. China has rejected these trilateral negotiations, asserting its nuclear capabilities are not on the same scale as those of the U.S. or Russia.

Despite the treaty's collapse, the U.S. and Russia agreed in Abu Dhabi to reestablish high-level military-to-military dialogue and may observe treaty terms for at least six months while discussing a replacement. UN Secretary-General António Guterres described the lapse as a "grave moment for international peace and security," warning that the risk of nuclear weapon use is at its highest in decades. Tensions remain high as the U.S. pursues a "Golden Dome" missile defense system in Greenland, while Russia warns of military-technical countermeasures.