New START Treaty Expires as US and Russia Fail to Reach New Nuclear Arms Deal

Washington/World — The landmark New Strategic Arms Reduction Treaty (New START) between the United States and Russia has officially expired as of February 5, 2026, with no immediate replacement deal in place, raising concerns among world leaders and security experts about a new era of unrestrained nuclear competition. (The Washington Post)

The treaty — first signed in 2010 and extended in 2021 — had been the last legally binding pact limiting nuclear arsenals between the two largest nuclear powers, capping each at 1,550 deployed nuclear warheads and 700 strategic delivery systems, and including rigorous verification mechanisms. (The Washington Post)

Breakdown in Talks

Earlier this year, Russian President Vladimir Putin proposed a voluntary one-year extension of the treaty’s limits after its scheduled expiration, a bid to preserve some form of restraint while negotiations continued. (The Economic Times)
However, U.S. President Donald Trump declined the extension offer, calling the original treaty “badly negotiated” and expressing a preference for negotiating a “modernized” agreement that could include additional nuclear powers such as China. (Reuters)

Moscow later said it received no formal U.S. response to its extension proposal and has warned of possible “military-technical countermeasures” if its security interests are threatened. (TASS)

Global Reaction and Risks

Russia’s Kremlin spokesperson has stated that Moscow will maintain a responsible nuclear stance, even as the treaty lapses, and has reiterated openness to future diplomatic engagement. (Reuters)
At the same time, international observers and the United Nations have described the expiration as a serious concern for global peace and security, emphasizing that the end of New START removes longstanding transparency measures and increases the risk of miscalculation or a renewed arms race. (ABC News)

What’s Next

The Trump administration has signaled its intention to pursue a new, more comprehensive nuclear arms control agreement, though details and timelines remain unclear — especially given China’s stated unwillingness to join talks and the broader geopolitical tensions surrounding Russia’s war in Ukraine. (Financial Times)

Experts warn that without a successor treaty or interim limits, the world’s two biggest nuclear arsenals are effectively unconstrained for the first time in decades, a development that could reshape strategic stability and global nonproliferation efforts. (The Washington Post)