Numerous nuclear experts are expressing serious concern over the presence of plutonium at nuclear sites in Iran, warning the Trump administration that the Islamic Republic could use the material to develop nuclear weapons and that any potential agreement to end the war must include provisions addressing the removal or monitoring of plutonium.

Most nuclear weapons are developed using enriched uranium, which has long been a central point of contention between Iran and the West. Tehran has repeatedly enriched uranium to levels that experts say could potentially be used in an atomic bomb.

However, experts note that plutonium can also be used to create a nuclear weapon. With so much international attention focused on Iran’s uranium stockpile, analysts argue that plutonium must receive a similar level of scrutiny.