Iran's main nuclear facility is expanding so quickly that United Nations inspectors have asked Teheran for improved safeguards against the production of weapons-grade uranium, the Telegraph reported Tuesday. The British newspaper explained that on a monthly basis, inspectors track Iran's installation of more centrifuges, used to enrich uranium, at the Natanz plant. The job of the UN's International Atomic Energy Agency inspectors is to make sure the centrifuges are not being used to produce the vital material for an atomic bomb. "As long as we are monitoring their facilities, they cannot develop nuclear weapons," the Telegraph quoted IAEA chief Mohammed ElBaradei as saying in a recent interview. However, due to Natanz's rapid growth - with an additional 984 centrifuges becoming operational since February, bringing the total to 4,920, and another 2,301 in various stages of preparation - the IAEA has said that it needs to boost its activities. "Given the increasing number" of centrifuges, "improvements to the containment and surveillance measures at the Fuel Enrichment Plant are required in order for the Agency to continue fully to meet its safeguards objectives," said the agency in its latest report. Sources quoted by the Telegraph said the inspectors were finding it increasingly difficult to monitor Natanz. Cameras have been installed to cover the plant's work, but they need adjusting to keep the new centrifuges under surveillance, they said, explaining that some parts of the facility were under construction while others were in full operation, and so the cameras need to be trained on the right locations. The IAEA report stated that inspectors had "proposed a solution and initiated discussions with Iran." In particular, they are believed to want Iran to allow "remote monitoring" of the Natanz plant, allowing them to send live footage to Vienna. Mark Fitzpatrick, director of the Non-Proliferation Program for the London-based International Institute for Strategic Studies, lamented that the lack of "real time monitoring" of Natanz meant the safeguards in place may not "give a timely warning" if Iran diverted its enrichment efforts towards making a nuclear weapon. The latest report says that all centrifuges and nuclear materials "remain under Agency containment and surveillance". The question is, for how long. "If Iran continues to refuse to allow remote monitoring of Natanz, as well as to refuse to clear up the other areas of concern such as the design information the IAEA has asked for, then there will be a loss of confidence in Iran," said Fitzpatrick.