TEHRAN, Iran (AP) -- Iran has begun installing 6,000 new centrifuges at its uranium enrichment plant in Natanz, state television quoted President Mahmoud Ahmadinejad as saying Tuesday.
The U.S. immediately criticized the announcement as an example of Iran's continued defiance of international demands that it suspend uranium enrichment, which can produce fuel for a nuclear reactor or fissile material for a weapon.
"Today's announcement reflects the Iranian leadership's continuing violation of international obligations and refusal to address international concerns," said Gregory Schulte, the U.S. representative to the Vienna-based International Atomic Energy Agency.
Iran already has about 3,000 centrifuges operating at its underground nuclear facility in Natanz, and the U.N. has passed three sets of sanctions against Iran for its refusal to suspend uranium enrichment. Tehran insists its nuclear program is focused on the peaceful production of energy, not the development of weapons as claimed by the U.S. and many of its allies.
"Iran has not only failed to suspend enrichment, but has chosen to ignore the will of the international community by announcing the installation of new centrifuges," said a spokesman for Britain's Foreign Office on condition of anonymity in line with policy.
"This is despite the fact that Iran's enrichment program has no apparent civilian purpose, and shows that Iran is making no effort to restore international confidence in its intentions," he said.
French Foreign Minister Bernard Kouchner said Iran's uranium enrichment effort is "dangerous" and continued sanctions may be necessary against Tehran.
Ahmadinejad made Tuesday's announcement as he toured the Natanz facility in central Iran.
"The president announced the start of the phase of installing 6,000 new centrifuges in Natanz," state television reported.
State television also quoted Ahmadinejad as saying that "we have reached new achievements" in Natanz that he would announce later Tuesday.
The president's trip was scheduled to coincide with Iran's National Day of Nuclear Technology, marking the second anniversary of Iran's first enrichment of uranium.
Ahmadinejad is widely expected to confirm for the first time Tuesday that Iran has installed hundreds of more sophisticated centrifuges that can enrich uranium faster.
The workhorse of Iran's enrichment program is the P-1 centrifuge, which is run in cascades of 164 machines. But Iranian officials confirmed in February that they had started using the IR-2 centrifuge that can churn out enriched uranium at more than double the rate.
Diplomats in Vienna told The Associated Press on Thursday that Iran has assembled hundreds of advanced centrifuges at Natanz.
One diplomat said more than 300 of the centrifuges have been linked up in two separate units in Iran's underground enrichment plant and a third was being assembled. He said the machines apparently are more advanced than the thousands already running underground.
But a senior diplomat said that while the new work appeared to include advanced centrifuges, they were not IR-2s.
Both diplomats are linked to the IAEA and asked for anonymity because their information was confidential.
A total of 3,000 centrifuges is the commonly accepted figure for a nuclear enrichment program that is past the experimental stage and can be used as a platform for a full industrial-scale program that could churn out enough enriched material for dozens of nuclear weapons.
Iran says it plans to move toward large-scale uranium enrichment that ultimately will involve 54,000 centrifuges.
Associated Press writers George Jahn in Vienna, Austria, and David Stringer in London contributed to this report.
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