The Treaty on the Non-Proliferation of Nuclear Weapons or NPT, designed to prevent the spread of nuclear arms, is approved by 191 states including the five formally recognized nuclear-weapon states. However, the NPT now faces a dire challenge, with Iran mulling a possible withdrawal from the pact amid US and Israeli attacks. Against this background, the 2026 NPT Review Conference will take place in New York from April 27 until May 22. Meanwhile, the New Strategic Arms Reduction Treaty, or New START, expired on February 5, without any sign of being extended, so far. Jim Walsh, senior research associate at MIT's Security Studies Program, tells CGTN host Tian Wei that the US and Israeli strikes on Iran's nuclear facilities could push Tehran to consider withdrawal from the NPT. If weakened or fractured, the treaty could trigger cascading effects significantly altering global security.