The UN atomic agency said yesterday that Iran has doubled its production capacity at a tough-to-bomb nuclear facility and has "significantly hampered" its ability to inspect a suspect military site. According to a new International Atomic Energy Agency report, as of August 18 the Fordo facility had about 2,000 uranium-enrichment centrifuges installed, compared with around 1,000 in May. Only about 700 are operating, however. Enriched uranium can be used for peaceful purposes but also, at highly concentrated purities, for nuclear weapons. Fordo is dug into a mountain near the holy city of Qom. Iran says its nuclear programme is for power generation and producing medical isotopes but Western nations, Israel and many others in the international community suspect its real aim is to develop the atomic bomb. Because the IAEA has repeatedly said that it was "unable" to conclude that Iran's activities were peaceful, the UN Security Council has called on Iran to cease all uranium enrichment, imposing four rounds of sanctions. The IAEA also wants Iran to address what it believes is evidence that until 2003, and possibly since, Tehran had a structured programme of research into nuclear weapons. Iran has flatly rejected these claims, set out in a major IAEA report last November, and says it will only give the agency the desired access as part of a broader agreement governing its future relations with the watchdog. In particular the IAEA wants to be able to visit the Parchin military base near Tehran where it believes Iran conducted explosives tests for nuclear warhead designs. Western nations accuse Tehran of "sanitising" the site to remove evidence and in the new report the IAEA says that Iran "has been conducting activities at that location that will significantly hamper the Agency's ability to conduct effective verification." The latest in a series of meetings aimed at persuading Iran to give the IAEA access to documents, scientists and sites involved in this alleged drive to get the bomb failed last Friday. A separate, higher-level renewed diplomatic push in talks between Iran and the "P5+1" five permanent members of the UN Security Council - the US, China, Russia, France and Britain - plus Germany appears stalled, meanwhile. After their first meeting in 14 months in Istanbul in April, further talks were held in Baghdad in May and in Moscow in June, where they were however downgraded to lower-level talks. Fresh talks between the P5+1 chief negotiator, EU foreign policy chief Catherine Ashton, and Iranian counterpart Saeed Jalili would happen "in the coming days," Ashton's spokesman said in Brussels yesterday.