U.S: Iran Still Not Fully Cooperating on Nukes

Despite allowing U.N. inspectors access to its nuclear facilities, Iran is still not fully cooperating, a senior Obama administration official said Friday.

"Iran is still not in compliance with its IAEA obligations and is not providing what has been called for, and that is full and comprehensive cooperation," the official told Reuters, referring to the International Atomic Energy Agency.

Iran's hard-line regime agreed in the last week to allow United Nations inspectors into two significant nuclear facilities, diplomats told FOX News.

United Nations inspectors have been granted access to Iran's heavy water facility at Arak, as well as the enrichment facility at Natanz -- the site of Iran's primary centrifuge installation.

Arak houses a nearly completed nuclear reactor. The site produces material for nuclear fuel that can be further enriched to provide fissile material for warheads. The past week's visit marks the first time in a year that international inspectors have been granted access to visit the heavy water reactor.

Additionally, diplomats have been granted greater monitoring rights at the site in Natanz, the location of centrifuge production and installation.

Since its clandestine enrichment efforts were revealed more than six years ago, Iran has steadily increased activities at its cavernous underground facility at Natanz, about 300 miles south of Tehran, shrugging off three sets of U.N. Security Council sanctions and rejecting talks meant to entice it to mothball the activity.

Before lifting that ban on visiting Arak, Tehran had repeatedly refused inspection requests from the IAEA, despite warnings by the agency that its stance contravened mutual agreements.

Western countries have repeatedly called on Iran to stop construction of the reactor, fearing it could be used as a second track toward building a warhead. When finished, say experts, Arak could produce enough plutonium for a nuclear weapon each year.

The Associated Press contributed to this report.