Israeli Prime Minister Benjamin Netanyahu has said Iran is using nuclear talks with world powers to "buy time" to work on building a nuclear bomb.
Netanyahu's remarks come after recent talks in Kazakhstan between Iran and six world powers ended with no breakthrough.
Israeli Defense Minister Ehud Barak, in a speech in Washington to the American Israel Public Affairs Committee, echoed Netanyahu in voicing doubt that diplomacy would stop Iran's nuclear ambitions.
Israel has threatened to strike Iran if it feels diplomacy is not working.
Iran has said its nuclear program is only for peaceful purposes.
Iranian media reported on March 4 the country was building around 3,000 new advanced enrichment centrifuges, a development that could accelerate the nuclear project.
The international standoff and shifting timelines are expected to dominate U.S. President Barack Obama's trip to Israel later this month.
Based on AFP and Reuters reporting