The flag of the International Atomic Energy Agency (IAEA) flutters in front of its headquarters in Vienna, Austria September 9, 2019. REUTERS/Leonhard Foeger

VIENNA (Reuters) - The U.N. atomic watchdog on Monday acknowledged Iran’s latest announcement on walking away, though reversibly, from its nuclear containment deal with major powers and said it would report any developments promptly to its member states.

The International Atomic Energy Agency is policing the landmark 2015 pact that placed restrictions on Tehran’s nuclear activities in exchange for lifting international sanctions against the Islamic Republic.

That deal has, however, been fraying since President Donald Trump pulled out the United States in 2018 and reimposed crippling economic sanctions on Tehran. The Islamic Republic has been responding since then by breaching the deal’s restrictions step by step. Its latest announcement came on Sunday.

“IAEA inspectors continue to carry out verification and monitoring activities in the country,” the Vienna-based agency said in a statement. “The IAEA will keep its member states informed of any developments in this regard in a timely manner as appropriate.”

Iran announced on Sunday that it would abandon limitations on enriching uranium but would continue to cooperate with the U.N. nuclear watchdog.

Iran has already breached many of the deal’s restrictions, including on the fissile purity to which it enriches uranium, its stock of enriched uranium, which models of centrifuge it enriches uranium with and where it enriches uranium.

It has, however, not gone far over the level of purity allowed – the deal sets a limit of 3.67% and Iran has stayed around 4.5% in recent months, well below the 20% it reached before the deal and the roughly 90% that is bomb-grade.

“The IAEA is aware of Iran’s announcement regarding a fifth step in reducing its commitments under the Joint Comprehensive Plan of Action (JCPOA),” the IAEA statement said, referring to the deal by its official name.

“The IAEA notes that the (Iranian) government statement also said that Iran’s cooperation with the agency will continue as before.”