Iran's vice president said Saturday his country needs 20 industrial-scale uranium enrichment facilities, a potentially dramatic expansion of its nuclear program in defiance of UN demands. Ali Akbar Salehi, who also heads the nuclear program, told the official IRNA news agency that Iran needs the sites to generate 20,000 megawatts of electricity through nuclear power plants over the next 20 years. The statement comes at a time of heightened Western concerns over Iran's nuclear intentions. President Mahmoud Ahmadinejad has said Iran is considering whether to scale back cooperation with the International Atomic Energy Agency (IAEA) after it approved a resolution censuring Iran over its nuclear program. Tehran argues its nuclear program is peaceful and insists it has a right to enrich uranium to produce fuel for nuclear reactors to generate electricity. The United Nations has demanded Iran freeze enrichment. Iran and the West are deadlocked over a UN proposal for Iran to send much of its enriched uranium abroad. The plan is aimed at drastically reducing Iran's stockpile of enriched uranium in hopes of thwarting the country's ability to potentially make a nuclear weapon. So far, Iran has balked at the offer. Last week, Tehran announced it intends to build the 10 new sites - a statement that followed a strong rebuke from the Vienna-based IAEA. It was not clear when or whether the government will approve the construction. But Iran's decision to dramatically expand its uranium enrichment program and scale back cooperation with the IAEA is widely seen as a slap to Western efforts to curtail Iran's nuclear program. Reformist jailed again Iranian authorities returned leading reformist Behzad Nabavi to jail Saturday after he was freed on bail following his arrest in the wake of disputed June elections, his party said. Nabavi, a senior official from the Organization of Mujahedeen of the Islamic Revolution party, had been sentenced to six years in prison for his part in protests against Ahmadinejad's reelection as the president. The former deputy parliament speaker was released for 10 days on Nov. 25 on a surety of $800,000 pending a possible appeal. “Today, as his 10-day leave ran out, Nabavi went to the revolutionary court... and he was told to go back to Evin prison,” the party said in a statement posted on its website. “He was told he has not observed necessary things during his leave, met with people outside his family, and made certain comments in these meetings apart from the usual greetings,” it said, without elaborating. In comments attributed to Nabavi after his release, he was quoted as saying arrest warrants for post-vote detainees were issued by an intelligence body several days before the June 12 election. Students Day crackdown Iranian opposition groups are preparing to hold fresh protests against Ahmadinejad Monday, several websites reported, as the nation marks the annual Students Day. The elite Revolutionary Guards and other authorities have warned they will crack down on any attempt by regime opponents to hijack the event to mount further demonstrations against Ahmadinejad's hotly disputed June reelection. Every year on Dec. 7, Tehran campuses mark the 1953 killing by the shah's security forces of three students, just months after a US-backed coup toppled the popular prime minister Mohammad Mossadeq. Opposition protesters have already taken advantage of a number of regime-sponsored events to organize demonstrations on the streets.