Updated

The U.N. nuclear agency has created a special Iran Task Force of nuclear weapons experts, intelligence analysts and other specialists focused on probing allegations that Tehran has been -- or is -- secretly working on developing atomic arms, according to an internal document shared with The Associated Press.

The announcement from the International Atomic Energy Agency says the elite squad started work Aug. 10. Dated Wednesday, the International Atomic Energy Agency statement says the unit will concentrate on implementing IAEA agreements with Iran, allowing it to monitor its nuclear activities as mandated by the Nuclear Nonproliferation Treaty.

It also says it will focus on "relevant" IAEA and U.N Security Council resolutions on Iran. Both have demanded that Tehran stop activities that could be used to make nuclear weapons and cooperate with the agency's investigation of suspicions Tehran worked on nuclear weapons.

But while drawing together its best experts, the new task force will have no more power regarding inspections of Iran's known or suspected nuclear sites than previous IAEA inspectors did.

Agency attempts to visit a site at Iran's Parchin military complex southeast of Tehran have documented IAEA limitations. For months, satellite images have recorded what the International Atomic Energy Agency suspects is an attempt to sanitize the site of suspected work on explosive charges used to detonate a warhead. At the same time, Iran has repeatedly rebuffed agency efforts for access -- including last Friday.

The most recent satellite images now show what diplomats last week said appears to be pink material shrouding buildings apparently linked to the alleged experiments, effectively blinding agency attempts to monitor a site that they have been kept from visiting. The diplomats demanded anonymity because they were not authorized to comment on the IAEA's Iran investigation.

Iran says such allegations are based on evidence fabricated by the United States and Israel and insists its nuclear program is meant only for making reactor fuel, medical isotopes and peaceful research. But it refuses to give up uranium enrichment, which can produce both reactor fuel and the core of nuclear warheads, despite offers of fuel from abroad. And it has stonewalled an IAEA probe into its alleged weapons work for more than four years, increasing concerns that it has something to hide.

Creating a unit focused on only one country is an unusual move for the IAEA, reflecting the urgency the U.N. nuclear watchdog is attaching to Iran amid fears that it is moving closer to the ability to make nuclear weapons, despite its denial. With diplomatic efforts to engage Tehran on its nuclear activities stalemated -- and Israel warning that it will not tolerate an Iran armed with atomic arms -- concerns are growing that time is running short to defuse tensions peacefully

Israel is particularly worried about a fortified bunker at Fordo, where Iran has begun producing uranium enriched to a level closer to the grade used in nuclear weapons than its main stockpile of fuel-grade material. About 70 kilometers (40 miles) south of Tehran, Fordo has about 800 centrifuges operating so far, enriching to a 20-percent level, and continues assembling others without operating them -- diplomats say that close to 3,000 are now fully or partially screwed together, including hundreds over the past three months

In Tehran, Iran's IAEA envoy, Ali Asghar Soltanieh, told reporters Tuesday that his country will "not suspend enrichment activities, even for a second."

Diplomats had told the AP last week that the IAEA was forming a special Iran team. The announcement confirming that information was forwarded Wednesday by a diplomat who demanded anonymity because he was not authorized to share confidential and internal IAEA documents. A phone call seeking comment from Soltanieh went to his voice mail.

Instead of focusing only one country, agency experts up to now have been tasked with following dozens of nations as they look for signs indicating secret attempts to make nuclear weapons.

Some IAEA officials feel that means that they often spend an inordinate amount of time monitoring countries that are unlikely to engage in such activities -- Western European nations, for instance -- meaning that not enough attention is paid to potential proliferators.

One of the diplomats who spoke to the AP last week said the Iran team will be comprised of about 20 experts drawn from the main IAEA pool.

The IAEA announcement said the squad will be headed by Massimo Aparo. A nuclear engineer, Aparo is an IAEA veteran who has held numerous senior positions linked to nonproliferation within and outside of the IAEA.

The agency said he will be reporting to IAEA Deputy Director General Herman Nackaerts, the head of the agency's nuclear inspectors and the agency's point man on Iran.