WASHINGTON -- Iran's supreme leader has apparently rejected key provisions of a framework agreement reached in April between his negotiators and those of six world powers.The rebuke, in a speech delivered live on Iranian television on Tuesday, specifically rejected limits on Tehran's research and development into nuclear technology that would last a decade or more. Ayatollah Ali Khamenei stated on Tuesday.R&D is explicitly limited four times in the White House document. Those limits specifically constrict R&D on enrichment for ten years, and R&D on advanced centrifuge technology for fifteen years.The document does not mention any "freeze" of R&D, though its use of advanced centrifuge models is also banned for "at least" ten years.Responding to Khamenei's comments, a State Department official told The Jerusalem Post that US negotiators were focused on their private discussions with their Iranian counterparts.“Our focus remains in the negotiating room, not on public comments," the official said. "We are committed to the understandings we reached in Lausanne and believe that it is the basis for a good deal. We will see, in the negotiations, if Iran does likewise."Khamenei also said that all sanctions— including US sanctions, imposed and lifted by the president as well as by Congress— would have to be lifted "immediately" upon the signing of a final deal.US President Barack Obama has already signed a bill into law which allows Congress to review any nuclear agreement with Iran, in its entirety, for thirty days after the deal is signed."All financial and economic sanctions imposed by the UN Security Council, the US Congress or the US government should be lifted immediately when we sign a nuclear agreement," Khamenei said.Khamenei also reiterated his opposition to any inspections at Iran's nuclear sites, characterizing his position as a "red line" in the historic talks.The US, Britain, France, Russia, China and Germany hope to clinch a final nuclear deal with Iran by June 30 in Vienna.According to parameters of the framework reached in Lausanne, Switzerland, released at the time by the White House, Iran at the time agreed to "limit domestic enrichment capacity and research and development... for ten years."But "freezing Iran's research and development (R&D) for a long time like 10 or 12 years is not acceptable,"