The United States is unsatisfied with Iran's offer to exchange low-grade enriched uranium for 20 percent enriched uranium on its southern island of Kish, saying it is "inconsistent" with a UN draft plan, according to local media on Saturday, Xinhua reported.
A senior U.S. official said in condition of anonymity that the Iranian offer "does not appear to be consistent" with a draft agreement proposed by the UN nuclear watchdog International Atomic Energy Agency (IAEA).
Iranian Foreign Minister Manouchehr Mottaki made the offer earlier Saturday in Bahrain, saying the country is willing to " take 400 kg of 3.5 percent enriched uranium to the island of Kish and exchange it with an amount equivalent to 20 percent of the original batch."
The process would begin "right away" if the six major powers, the United States, Britain, France, China and Russia and Germany agree to the offer, he added.
The IAEA has drafted an agreement which calls for shipping most of Iran's existing low-grade enriched uranium to Russia and France by the end of the year, where it would be processed into fuel rods with a purity of 20 percent.
The higher-level enriched uranium would be transported back to Iran to be used in a research reactor in Tehran for the manufacture of medical radioisotopes.
Iran rejected the deal, demanding a simultaneous exchange between low and higher level enriched uranium inside the country.
The U.S. official also noted the IAEA deal called on Iran to send out its low enriched uranium "in one batch."