Iran's first nuclear power plant is set to be launched by late September now that an important final test has been carried out at the reactor, the head of the Islamic state's Atomic Energy Organization said on Wednesday. Ali Akbar Salehi's statement, at the site near the port city of Bushehr, suggested that a row that erupted between Moscow and Tehran in May over new UN sanctions against Iran had caused no further delays to the project. “We reached the point of no return and the ground is paved for the reactor to go on stream,” the official IRNA news agency quoted Salehi as saying, adding the start-up would take place during the Iranian month which begins on Aug. 23. He said warm-water tests had been conducted on the facility, adding they were “the last and some of the most important tests before going on stream.” Acknowledging for the first time the impact of the punitive measures, Salehi said the new sanctions “may slow down” Tehran's nuclear program but “not stop it.” “One can't say sanctions are ineffective,” Salehi said. “If sanctions are aimed at preventing Iran's nuclear activities... we say they may slow down the work, but will not stop the activities. This is a certainty.” Russia agreed to build the 1,000-megawatt reactor 15 years ago but delays have haunted the $1 billion project and diplomats say Moscow has used it as a lever in relations with Tehran. The head of Russia's state nuclear corporation, Sergei Kiriyenko, said this year the Bushehr reactor was scheduled to begin operating in August. In March, US Secretary of State Hillary Clinton criticized Russia's plans to start up Bushehr, saying it was “premature” without further assurances on Tehran's nuclear program. Iran says its atomic activities are aimed at generating electricity, not developing arms, as Western powers suspect. Russia is a permanent member of the United Nations Security Council, which on June 9 adopted a fourth round of sanctions on Iran over its refusal to suspend the nuclear work.