Iran began testing its first nuclear power plant Wednesday in the face of deep international concern over its atomic drive and said the long-delayed project could go on line within months. Officials from Iran and Russia, which has been involving in building the power station for the past 14 years, watched over the start of the pre-commissioning in the port of Bushehr. “As for a timetable, the tests should take between four and six, seven months,” the head of Iran's Atomic Energy Organisation Gholam Reza Aghazdeh said at a press conference in Bushehr. “And if they go smoothly, then it (the launch of Bushehr) will be even sooner.” He also said Iran is now operating 6,000 centrifuges to enrich uranium, defying international calls that it halt the sensitive nuclear process which is at the heart of Western fears it is secretly trying to build the atomic bomb. “We have 6,000 centrifuges working and we plan to increase them. In the next five years we plan to have 50,000 centrifuges,” Aghazdeh told reporters. Iran has rejected repeated calls by the UN Security Council – of which Russia is a permanent member – for a halt to enrichment, despite three sets of sanctions being imposed for its defiance. The UN nuclear watchdog had said in a report last week that Iran was slowing the expansion of its enrichment activities, with 3,964 centrifuges actively operating in Natanz. The visiting head of the Russian nuclear agency, Sergei Kiriyenko, announced that construction of the 1,000-megawatt Bushehr plant had been completed.