A view of the Arak heavy-water project
A view of the Arak heavy-water projectReuters

Iran has shipped 11 tons of heavy water abroad to bring its stock back under a limit set by its nuclear deal with major powers, a diplomat citing a confidential UN nuclear watchdog report told Reuters on Tuesday.

A recent report from the UN's International Atomic Energy Agency (IAEA) found that Iran had exceeded its heavy water limit by 100 kilograms (220 pounds) over the 130 metric tons allowed under last year's nuclear agreement.

Subsequent reports said that Iran transferred 11 tons of heavy water to Oman in order to meet the limit.

The diplomat told Reuters that the latest IAEA report substantiated Iran’s statement about a transfer to Oman but does not identify the destination of the heavy water.

Iran’s violation is a small but significant one, and last month marked the second time in recent months that Iran exceeded the amount of heavy water it is allowed to possess under the deal.

"On December 6 the agency verified the quantity of 11 metric tons of the nuclear-grade heavy water at its destination outside Iran," the diplomat quoted the five-paragraph report by the IAEA to member states as saying.

"This transfer of heavy water out of Iran brings Iran's stock of heavy water to below 130 tons," it said, according to Reuters, adding that Iran had told the agency that the shipment left the country on November 19.

Though the United States and its allies will see the shipment as a move in the right direction, it is not enough to satisfy them. Washington has underlined that the deal says excess heavy water must be delivered to a foreign buyer, and Iran has made clear Oman is not the final destination.

Despite the two violations, the IAEA indicated this past September that Iran had kept to the nuclear deal.