International Atomic Energy Agency

The U.N. nuclear agency signaled Friday that it was preparing to cancel technical aid on nearly half its nuclear cooperation projects with Iran, a significant step toward implementing sanctions aimed at halting the nation's controversial uranium enrichment program.

In a fresh sign of easing tensions, North Korean officials Friday invited the chief of the U.N. nuclear watchdog agency to visit Pyongyang next month to develop plans aimed at dismantling the nation's nuclear weapons program, officials said here.

Although international concern is growing about Iran's nuclear program and its regional ambitions, diplomats here say most U.S. intelligence shared with the U.N. nuclear watchdog agency has proved inaccurate and none has led to significant discoveries inside Iran. The officials said the CIA and other Western spy services had provided sensitive information to the Vienna-based International Atomic Energy Agency at least since 2002, when Iran's long-secret nuclear program was exposed.

Iran's efforts to trumpet its nuclear program are cementing the country's confrontation with the West regardless of whether its claims this week of technological progress are true, several analysts said Tuesday. The head of Iran's atomic energy program on Tuesday reiterated Tehran's long-held claim that it eventually will install 50,000 centrifuges, used to enrich uranium, at its facility in Natanz.

Iran is delivering small amounts of uranium gas to centrifuges that can enrich it to weapons-grade level and is running 1,312 of the machines, according to a confidential International Atomic Energy Agency document obtained Wednesday. The document -- a letter to Iranian officials from a senior IAEA staff member -- protests an Iranian decision to prevent inspectors from visiting the country's heavy-water facility, which will produce plutonium.

Defying the international community, Iran has sharply upgraded its capacity to enrich uranium in recent months while the outside world's access to and grasp of Tehran's nuclear program "has deteriorated," according to an unusually blunt report Wednesday by the International Atomic Energy Agency. As two U.S.

The head of the United Nations nuclear inspection agency warned for the first time Thursday that Iran probably can enrich enough uranium to build a nuclear bomb in three to eight years, a judgment that sparked fresh concerns about Tehran's nuclear ambitions. Mohamed ElBaradei, director of the Vienna-based International Atomic Energy Agency, gave his assessment a day after a strongly worded IAEA report cautioned that Tehran had reduced its cooperation with U.N.

As Iran races ahead with an illicit uranium enrichment effort, nearly a dozen other Middle East nations are moving forward on their own civilian nuclear programs. In the latest development, a team of eight U.N. experts on Friday ended a weeklong trip to Saudi Arabia to provide nuclear guidance to officials from six Persian Gulf countries.

North Korea on Saturday invited U.N. nuclear inspectors to visit in the first concrete sign of a breakthrough in a stalemate over its atomic program, as the transfer of frozen North Korean funds at the center of the impasse neared completion. North Korea sent a letter to the Vienna-based International Atomic Energy Agency, inviting inspectors to discuss shutting down its main nuclear reactor, since "it is confirmed that the process of de-freezing the funds ...

Iranian officials said Sunday that any further United Nations Security Council sanctions on the country could jeopardize its recent decisions to grant international inspectors greater access to nuclear sites and disclose information about past activities. Iran last week announced a decision to allow inspectors from the International Atomic Energy Agency, the U.N.'s nuclear watchdog, to monitor its heavy-water reactor near the western town of Arak, after having barred them this year.