Iran has agreed to let the United Nations atomic agency monitor its production of critical centrifuge parts, ending a three-month deadlock and averting a fresh diplomatic clash with the U.S.

The Iranian move offers a sliver of hope for negotiations between Iran, the U.S. and other powers on restoring the 2015 nuclear accord, by removing one of the plethora of issues of concern to Western officials. Diplomats say those talks remain deadlocked.

The International Atomic Energy Agency said Iran has agreed to allow inspectors to replace cameras before the end of the month at an assembly plant in Karaj, a city west of Tehran, where rotors and bellows for centrifuges are made, allowing the agency to monitor activity. Centrifuges are used to enrich uranium to higher levels of purity.

Iran resumed the production of advanced centrifuge parts at Karaj in late August, with no international monitoring. That raised the prospect of centrifuges being manufactured and set aside for a future covert nuclear-weapons program, although there is no evidence of Iran doing that.