In an interview published in today's "Financial Times," the head of the International Atomic Energy Agency said Iran must answer key questions about its uranium-enrichment program before the end of this year or face new penalties.
El-Baradei said he expected Iran to clear up suspicions about its acquisition of advanced centrifuges before he reports to the IAEA governing board on November 22.
He said the two key issues that Tehran must clarify in the next few weeks were the extent of its research and development capabilities on enrichment and its capacity to build weapons from nuclear material.
And he said the key was for Iran to show that it is working with the UN nuclear watchdog "in good faith, with good intentions."
But el-Baradei also said that if Iran failed to deliver on its promises to answer those questions, its unwillingness to cooperate would "backfire in their face."
He said: "I've told the Iranians, 'This is your litmus test. You committed yourself to come clean. If you don't, nobody will be able to come to your support.'"
Rebuff For Iran's Leader
El-Baradei's remarks are seen as his strongest rebuff to date against Iranian President Mahmud Ahmadinejad.
Ahmadinejad told the UN General Assembly in New York on September 25 that Tehran believed "the nuclear issue of Iran is now closed and has turned into an ordinary agency matter" for the IAEA.
Although questions remain unanswered, Ahmadinejad insisted that Tehran has no interest in developing nuclear weapons and that all of its nuclear activities are "peaceful and transparent."
"In the last two years, because of abuse of power on the [UN] Security Council, arrogant powers have tried to intimidate with military action and threatened economic sanctions," he said. "But because of its belief in God and national unity, Iran continued to walk forward, step by step. And now Iran as a country has the industrial-scale, fuel-cycle capability for peaceful purposes."
In August, el-Baradei agreed to a plan with Iran under which Tehran would answer questions about its nuclear program from as far back as the 1980s. That move irritated the United States and some European Union countries, which see the plan as an opportunity for Iran to continue enriching uranium.
But the plan has been viewed favorably by Russia and China, which are permanent, veto-wielding members of the UN Security Council.
On September 30, Iranian Foreign Ministry spokesman Mohammad Ali Hosseini told reporters that Tehran would cooperate with the IAEA in order to put a stop to any possible sanctions.
The UN Security Council already has passed two resolutions imposing sanctions against Tehran as punishment for its refusal to suspend sensitive uranium-enrichment activities.