All NNWSs party to the NPT, as well as States party to the regional  nuclear-weapon-free zone treaties (NWFZ Treaties), are required to conclude Comprehensive Safeguards Agreements (CSAs) with the IAEA. Such agreements are concluded on the basis of  INFCIRC/153 (Corrected). A State undertakes to accept IAEA safeguards on all nuclear material in all peaceful nuclear activities within its territory, under its jurisdiction or carried out under its control anywhere. Under these agreements, the IAEA has the right and obligation to ensure that safeguards are applied on all such nuclear material for the exclusive purpose of verifying that such material is not diverted to nuclear weapons or other nuclear explosive devices.

Source: IAEA