Work Commences on Arak Reactor Modernization

The temporary shut-down of the Arak heavy water production plant for maintenance marks the start of the redesigning of its heavy water reactor, a lawmaker said.

Under the 2015 nuclear deal with major powers, Iran received relief from international sanctions in return for temporary curbs on its nuclear program, which included a call to redesign and reconstruct the Arak reactor.

Iran's compliance with the accord is being monitored by the International Atomic Energy Organization.

The Vienna-based agency, in its latest report on Friday, verified that Tehran has kept to the agreement.

It also said Iran is not now producing heavy water because its production plant has been shut down for maintenance.

"The repair and maintenance of the heavy water [plant] is the first step in the redesign of the [reactor] structure," Hossein Naqavi Hosseini, spokesman for Majlis National Security and Foreign Policy Commission, was quoted by IRNA as saying on Monday.

Tehran, Washington and Beijing released a joint "statement of intent" on Oct. 18, 2015 to announce cooperation on the Arak project and shortly afterward a related document signed by all the parties to the nuclear agreement was published.

The document said the six nation parties to the pact, namely the US, Britain, France, China and Russia plus Germany, are required to contribute to the project through a working group established after consultations with Iran and co-chaired by the US and China.

China is participating in the design and construction of the modernized reactor and, as the primary liaison between the working group and Iran, facilitates communications in the course of the project's implementation.

Iran and China signed a long-awaited deal in late April to go ahead with the joint implementation of the Arak Modernization Project.

  Positive Sign

"We have been waiting for the Arak deal to take effect … the announcement that the Arak heavy water plant is closed for repair and maintenance shows that the redesign project has become operational," Naqavi Hosseini added.

While the Friday report confirmed that Iran's nuclear program has stayed within the limits set by the nuclear accord, Reuters cited it as saying that Iran is allegedly close to breaching a cap on its heavy water stockpile.

The report was the second since the January inauguration of US President Donald Trump, who has described the pact negotiated under his predecessor Barack Obama as "the worst deal ever negotiated".

Iran's stock of low-enriched uranium as of May 27 was 79.8 kg, well below a 202.8-kg limit, and the level of enrichment did not exceed a 3.67% cap.

But Iran's stock of heavy water, a chemical used as a moderator in a type of nuclear reactor that can produce plutonium, reached 128.2 tons, just below a 130-ton limit, the IAEA report said.

Plutonium can be used as an alternative to uranium for producing nuclear bombs.

Iran denies having ever considered developing a nuclear warhead and says its nuclear program is only meant for civilian purposes.

The deal calls for any excess amount of heavy water to be sold to a foreign buyer, and Iran has shipped the surplus to Oman while it looks for prospective buyers.

The Trump administration indicated its support for the Oman arrangement in April by acknowledging Iran was meeting its commitments under the nuclear deal.