EDITORS' NOTE: Reuters and other foreign media are subject to Iranian restrictions on leaving the office to report, film or take pictures in Tehran.

Iranian President Mahmoud Ahmadinejad speaks during a ceremony to mark the Fourth National Anniversary of Nuclear Technology, in Tehran April 9, 2010. Iran announced Friday it had developed faster centrifuges for uranium enrichment, signalling determination to press on with its nuclear work despite possible new U.N. sanctions sought by U.S. President Barack Obama. REUTERS/Morteza Nikoubazl (IRAN - Tags: ANNIVERSARY POLITICS ENERGY)