Iran has resumed work on making advanced equipment that nuclear experts say is principally used for developing atomic weapons, the The Telegraph reported Monday, citing intelligence reports received by Western diplomats. The British newspaper said that the goal of the work was to develop the blueprint provided by Pakistani scientist Dr. Abdul Qadeer Khan, the so-called father of Pakistan's nuclear bomb, who sold Iran information on building atom bombs in the early 1990s. The Iranian Revolutionary Guard Corps (IRGC) has established several civilian companies to work on the program, continued the Telegraph , adding that the companies' operations were being intentionally hidden from UN nuclear inspectors. The paper went on to say that the companies, based outside Teheran, were working on constructing components for the advanced P2 gas centrifuge, which can enrich uranium to weapons grade two to three times faster than conventional P1 centrifuges. Iran's nuclear enrichment program at Natanz runs on P1 centrifuges, but Iranian nuclear scientists recently conducted successful tests on a prototype P2 centrifuge at the site. The IRGC has now set up a network of companies to build components for the advanced centrifuges, raising Western concerns that Iran is continuing work on its nuclear weapons program, continued the Telegraph. "If Iran's nuclear intentions were peaceful, there would be no need for it to undertake this work in secret," the newspaper quoted an official familiar with the intelligence reports as saying. A previous secret attempt by Iran to develop P2 centrifuges was halted in 2004 after a civilian company set up by the IRGC was exposed. UN nuclear inspectors found traces of weapons-grade uranium at the company when they inspected the site. According to recent intelligence reports, said the Telegraph , Iranian President Mahmoud Ahmadinejad personally ordered the IRGC to set up companies for the clandestine construction of components for P2 centrifuges this year. The paper claimed that one of the companies was located in a residential building in Amir Abad, western Teheran, where its work is unlikely to be detected by UN inspectors, adding that another of the facilities was reportedly run by a company owned by the IRGC. The Telegraph reported that the operation was a direct copy of the IRGC's previous attempt to develop P2 centrifuges, when research work was undertaken by the Kalaye Electric Company, which claimed it was manufacturing watches. When its actual operations were revealed to UN inspectors in 2004, they found the company had managed to build the centrifuges and enrich small quantities of uranium to weapons grade. Senior officials from Iran's Atomic Energy Agency are supervising the current clandestine program, based on the atomic weapons blueprint sold to Iran by Khan in 1994, reported the Telegraph .