President Mahmoud Ahmadinejad has ignored threats of sanctions by the US and declared Iran a “nuclear state” having produced its first batch of level-20 enriched uranium. “Western experts have already said that once Iran was able to enrich uranium to 20 percent it could theoretically also move relatively quickly toward the manufacture of weapons-grade fuel, usually reckoned to require 90 percent purification. The process at the Natanz facility south of Tehran took place in the presence of inspectors from the International Atomic Energy Agency, the United Nations nuclear oversight body. I.A.E.A. officials said Thursday they could not confirm the Iranian claim. ‘Right now at Natanz we have the capability to enrich uranium to much higher levels,’ Mr. Ahmadinejad told tens of thousands of supporters in Tehran’s Azadi Square, saying “it was reported that the first consignment of 20 percent enriched uranium was produced and was put at the disposal of the scientists,’ Reuters reported. ‘In the near future we will treble its production,’ Mr. Ahmadinejad said. In a note distributed to the agency’s member states late Wednesday, the director general of the I.A.E.A., Yukiya Amano, said that when the inspectors arrived at the Natanz on Wednesday, they were informed that Iran had already begun to feed low-enriched uranium into a cascade of centrifuges for enrichment, ostensibly for use in a medical reactor.”