Iran ? Iran’s president said Saturday his country now possesses 6,000 centrifuges, a significant increase in its nuclear program that is certain to further rankle the United States and others who fear Tehran is intent on developing weapons.

The new figure is double the 3,000 uranium-enriching machines Iran had previously said it was operating.

President Mahmoud Ahmadinejad’s announcement, reported by the semi-official Fars news agency, comes a week after the U.S. reversed course in negotiations over Iran’s nuclear program by sending a top American diplomat to participate in talks between Tehran and world powers.

The bend in policy had prompted hopes for a compromise under which Iran would agree to temporarily stop expansion of enrichment activities. But the White House said Saturday’s development did not facilitate a resolution.