Reports in Russia said earlier Monday that the Islamic Republic had not made payments under the $1 billion project in Bushehr for over a month already.
"Obviously, difficulties facing the Iranian side are affecting the construction timetable," Atomstroyexport's Vladimir Pavlov said.
Russia is building Iran's first nuclear power plant under a contract signed in 1995. The plant is scheduled to be commissioned in the second half of 2007, after the original date at the end of 2006 was put off.
"The Iranian side has not been making payments for the building of the Bushehr NPP," the source told RIA Novosti, adding that difficulties emerged after Iran prohibited payments in U.S. dollars and made a transition to payments in euros.
Pavlov confirmed the report, as well as problems with supplies of refrigeration systems to Bushehr. "We are very concerned about this, and are waiting for proposals from the Iranian side," he said.
Andrei Cherkasenko, head of AtomPromResurs, a manufacturer of equipment for the nuclear power industry in Russia, said Monday supplies of refrigeration systems from third countries is also a serious restriction.
"As far as I know, supplies are scheduled for late 2007 - early 2008 under contracts signed by the Iranian side," Cherkasenko said.
He said the NPP may be launched no sooner than several months after the delivery of refrigeration equipment.
A source in the Russian nuclear industry said Iran's representatives plan to visit Russia soon to discuss the construction of the Bushehr NPP.
"We are concerned with the situation regarding the Bushehr NPP's financing. As of today, it [financing] has been frozen, though work on the site continues. Our Iranian partners have promised to come to Russia in February to discuss the construction of the nuclear power plant," the source said.
The Bushehr facility has been a source of international dispute, with the United States and other Western countries, raising concerns that Iran could use the project as part of a covert weapons program. Iran has consistently denied that its nuclear program has military goals.
The UN Security Council adopted a resolution in December imposing sanctions against Iran.
Russia, a key economic partner of Iran, has consistently supported the Islamic Republic's right to nuclear power under the Nuclear Non-Proliferation Treaty (NPT), and has resisted the imposition of harsh sanctions.
