TEHRAN (Reuters) - A team from the UN nuclear watchdog inspected a nuclear site in Iran on Sunday that has heightened Western fears of a covert programme to develop atomic bombs, the semi-official Mehr news agency reported. Iran added to global concerns over its nuclear intentions in September by revealing the existence of the site in central Iran after Western spy services penetrated a three-year veil of secrecy. The inspectors ... visited the facility in central Iran. They are expected to visit the site again, Mehr reported, without giving a source. There was no immediate confirmation from the International Atomic Energy Agency (IAEA). The IAEA inspectors arrived in Iran early on Sunday to examine the site, under construction 160 km (100 miles) south of Tehran. Refined uranium can be used to fuel nuclear power plants and also to provide material for bombs if enriched further. Iran, which says it wants only peaceful nuclear energy, agreed to open the new site to monitoring at talks with six world powers - the United States, Germany, France, Russia, China and Britain - held in Geneva on October 1. But a second understanding struck in the Swiss city stumbled on Friday when Iran cast doubt on a plan to send abroad much of its enriched uranium reserve for processing into special fuel for a reactor used to create radioactive isotopes for medical purposes. Influential Iranian lawmakers have criticised the UN-drafted nuclear fuel agreement, in comments echoed by an Iranian diplomat on Sunday. Abolfazl Zorehvand, a former ambassador to Italy, said the plan amounted to a kind of suspension of Irans enrichment work - a demand the Islamic state has repeatedly rejected. If we want to enrich this amount again it would take at least 18 months. During these 18 months they will have time to pressure Iran again and push us in the direction they want to, the official IRNA news agency quoted Zorehvand as saying. These signals from the West create mistrust, he said. A member of parliaments foreign affairs and national security commission made clear he opposed the draft agreement. Im against accepting the deal ... It is not in Irans interest, ISNA news agency quoted MP Mohammad Karamirad as saying. Iran has said the centrifuge plant being built in a military compound buried inside a mountain near Qom would refine uranium only for civilian nuclear energy. Western diplomats and analysts say the sites capacity appears too small to fuel a nuclear power station but enough to yield fissile material for one or two nuclear warheads a year. The four-strong team from the International Atomic Energy Agencys safeguards division, led by Herman Nackaerts, who oversees the Middle East region including Iran, declined comment to reporters in Vienna before boarding their flight. Their stay in Iran is likely to last several days. A senior lawmaker said Iran, with the UN inspections, sent a message of confidence-building, good interaction and transparency and it would be good that the Westerners receive this message correctly, IRNA news agency reported. MP Hassan Sobhaninia added: The inspectors can see for themselves... (the) new facilities and like always before become aware of the peaceful nature of Irans nuclear activities.