Iran approved a resolution accepting foreign participation in its nuclear enrichment plant, the most controversial step in the country's atomic program, state-run radio reported Saturday. Under the resolution approved on Wednesday, Iran's Atomic Energy Organization is authorized to attract domestic and foreign investors in the Natanz enrichment facility in central Iran. The move follows the Iranian government's approval last month of an outline of a law on fixing the method of involvement by foreign countries and companies in its nuclear program, which the United States suspects is a front for developing weapons. Iran denies the weapons claims, saying it is interested only in generating electricity. Iranian authorities will decide on the size of the stake any partner would take, the radio added without elaborating. Iran has said it won't restart uranium enrichment for now at Natanz, where the process was suspended in 2003 under a deal with Europeans. Tehran plans to run 50,000 centrifuges to enrich uranium in Natanz, which Iran says is designed to meet the fuel requirements of the Bushehr nuclear reactor built in the south of the country with Russian help. Hard-line President Mahmoud Ahmadinejad first raised the idea of letting foreign countries and companies play a role in Iran's nuclear program in September, calling it a way to assure the world that the nuclear program would be for peaceful purposes only. Iran resumed uranium-reprocessing activities at its Uranium Conversion Facility in Isfahan in central Iran in August. The facility converts uranium concentrate ore, known as yellowcake, into uranium hexafloride gas, the feedstock for enrichment. In the next stage, Iran could feed the gas into centrifuges used to enrich uranium at Natanz. Uranium enriched to low levels goes toward producing nuclear fuel used to generate electricity, but further enrichment makes it suitable for use in nuclear weapons. Iran also has rejected as "illegal and illogical" an International Atomic Energy Agency resolution last month that puts it just one step away from referral to the UN Security Council for possible sanctions. To avoid referral, Iran is being told to suspend all uranium enrichment activities including uranium conversion, to give up construction of a heavy water nuclear reactor and to allow more extensive inspections of its nuclear facilities. Iran's government has already threatened that unless the UN nuclear agency backs down, it will resume uranium enrichment and block inspections. The IAEA resolution was passed after Iran rejected a European package that called on Iran to permanently give up uranium enrichment. Talks between Britain, Germany, France and Iran collapsed in early August after Iran resumed uranium-reprocessing activities at a site in Isfahan.