Iran Preparing for Advanced Nuclear Work, Officials Say

ISTANBUL, Turkey — Iran has plans to install tens of thousands of advanced centrifuges at its huge underground nuclear plant near the central city of Natanz, which eventually would enable the nation to enrich uranium nearly twice as fast as anticipated, Western intelligence officials say.The officials say there is no hard evidence that Iran is currently manufacturing the updated centrifuges and that the timetable for installation remains unknown. However, preparatory work is underway at the plant, they said in recent interviews, and the decision to rely on the superior type of centrifuge suggests Iran could manufacture fissile material for a possible weapon sooner than expected...