The motion brought by Britain, France and Germany -- but opposed by China and Russia -- is the first of its kind since November 2022 and comes amid an impasse over Iran's escalating nuclear activities.

Western powers fear Tehran might be seeking to develop a nuclear weapon -- a claim the Islamic Republic has always denied.

The resolution was carried by 20 votes in favour -- including the United States which initially was reluctant -- with 12 abstentions and one country absent, diplomats told AFP.

The confidential resolution obtained by AFP reiterates it is "essential and urgent" that Tehran provides "technically credible explanations" for the presence of uranium particles found at two undeclared locations in Iran.

"A continued failure" by Iran to provide full cooperation on the years-long probe "may necessitate" a comprehensive assessment by the IAEA head Rafael Grossi, the text stresses.

Furthermore, Iran has to "reverse its withdrawal of the designations of several experienced Agency inspectors", and "without delay" reconnect the cameras used to monitor nuclear activities.

The text also notes the "concerns" surrounding "recent public statements made in Iran... regarding its technical capabilities to produce nuclear weapons and possible changes to Iran's nuclear doctrine".

Although symbolic in nature at this stage, the censure motion is designed to raise diplomatic pressure on Iran, with the option to potentially refer the issue to the UN Security Council down the line.

Iran has gradually broken away from its commitments under the nuclear deal it struck with world powers in 2015.

The landmark deal provided Iran sanctions relief in exchange for curbs on its atomic programme, but it fell apart after the unilateral withdrawal of the United States under then-president Donald Trump in 2018.

Efforts to revive the deal have so far failed.