The world’s most infamous nuclear smuggler is still haunting Iran, with diplomats weighing whether to censure the nation over mysterious uranium particles discovered by international investigators at an undeclared site.

Some of those particles date back to Iran’s dealings with Abdul Qadeer Khan, the father of Pakistan’s atomic weapons program, who died in October, according to diplomats and former officials from the International Atomic Energy Agency.

Khan began smuggling sensitive nuclear technologies out of Europe almost a half century ago, supplying Iran and North Korea with centrifuge designs and components.

Iran’s dealings with Khan were the subject of a 12-year probe by the IAEA which only ended after Tehran agreed in 2015 to limit its atomic work in exchange for sanctions relief. The fact that atomic traces are still popping up unexpectedly underscores why some countries still doubt Tehran’s assertion that it has no plan to build a bomb.

“Iran has not provided explanations that are technically credible,” IAEA Director General Rafael Mariano Grossi wrote to diplomats this week in a restricted report seen by Bloomberg. “The agency cannot confirm the correctness and completeness of Iran’s declarations under its comprehensive safeguards agreement.”

Tehran’s failure to clarify how the traces came to be at an undeclared storage depot south of the capital has raised pressure on diplomats to proceed with a formal censure when the IAEA board next meets on June 6.

A draft resolution circulated by diplomats this week in Vienna criticizes Iran for “systematic insufficient cooperation” with IAEA monitors, while calling for it to step up assistance to their investigation.

The issue could eventually be referred to the United Nations Security Council, potentially escalating tensions just as the probability of reviving the international accord capping Iran’s nuclear activities is diminishing.

The latest IAEA report is “a matter of great concern that Iran needs to clarify “without delay,” the French Foreign Ministry said Tuesday. The US State Department similarly urged Iran to cooperate with investigators and said it’s still assessing whether to censure the Islamic Republic.

The particles show how the ultra-long life of radioactive material allows monitors to detect unusual activities even years after they’ve taken place.

Forensic scientists have identified the samples taken at the Turquzabad depot as isotopically similar to material that was detected 20 years ago and conclusively linked to Khan’s nuclear-smuggling network, according to one diplomat, who asked not to be identified to discuss the probe.

A briefing prepared for international envoys highlighted the significance of Khan’s operations to Tehran.

Iran was able to develop its nuclear program only after receiving “massive assistance” from the AQ Khan network in Pakistan which supplied “centrifuges for enrichment, necessary bespoke electronics, uranium gas handling systems and a great deal of advice,” the report seen by Bloomberg said.

The so-called atomic warehouse in Turquzabad was first identified publicly by former Israeli Prime Minister Benjamin Netanyahu in September 2018.

The IAEA subsequently linked the site – located about 22 miles (35 kilometers) south of Tehran in an industrial zone piled with containers and scrap – to other places of interest to investigators.

Iran has told the IAEA that the contamination likely came from scrap metal stored at the site, an explanation that investigators say is only plausible if Iran produces supporting documentation to prove the claim.

It was international doubt over Iran’s intentions and transparency that eventually led to the 2015 nuclear agreement, which also provided for unprecedented international monitoring of Iranian atomic activities.

Despite concern over the samples, US intelligence agencies continue to conclude that Iran stopped developing the military dimensions of its atomic program in 2003.

That leaves diplomats meeting next week in Vienna with a hard choice to make, said the former IAEA official: either re-litigate the origin story of Iran’s nuclear program, or try to reinstate the unprecedented inspector access made possible under the atomic agreement. Both options may not be possible.

Source » trackpersia