In September, senior Russian officials rejected a claim that Moscow could stop construction work if the UN imposed sanctions on the Islamic republic over its refusal to halt uranium enrichment or if it expelled IAEA inspectors.
"All launch delays of the Bushehr nuclear power plant in Iran are of a technical or management nature," Sergei Shmatko said, adding that the Bushehr project is unique in terms of technology and construction techniques.
Atomstroiexport is building Bushehr's first power unit under a $1 billion contract signed by Russia and Iran in 1995. The NPP is being constructed under the supervision of the IAEA, the UN's nuclear watchdog.
Russia's nuclear chief Sergei Kiriyenko said last month the plant will be commissioned in September 2007, with the power generating launch to take place two months later.
The plant was originally scheduled to be commissioned at the end of 2006.
Iran has been at the center of an international dispute this year over its nuclear ambitions. Some countries suspect the Islamic republic of pursuing a covert weapons program, but Tehran has consistently denied the claims and says it needs nuclear energy for civilian needs.
The U.S. and other UN Security Council members have pushed for sanctions against Iran, but have met with resistance from veto-holding members Russia and China.
The UN adopted a resolution on Iran July 31 demanding that the country suspend uranium enrichment by August 31 or face sanctions. But Tehran, which denies that its nuclear project is aimed at producing weapons, refuses to comply.
The United States and Britain renewed calls for sanctions against a defiant Iran when negotiations between the country's key nuclear negotiator, Ali Larijani, and EU foreign policy chief Javier Solana failed to produce any breakthrough.
Iran's student news agency ISNA has fueled more fears around the country's controversial nuclear program, quoting on Wednesday an informed source as saying Tehran has installed a second cascade for uranium enrichment and will start injecting uranium gas into it within days.
Kiriyenko, who is the head of the Federal Agency for Nuclear Power and co-chairman of a Russian-Iranian intergovernmental commission, is set to visit Iran in December to discuss bilateral relations.
