"This is a very difficult process, so I think to speak of a concrete date for the launch is still early," Dan Belenky, head of state-owned nuclear contractor Atomstroiexport, told the Interfax news agency.

Belenky's comments were in contrast to earlier statements by Tehran claiming that the facility in Iran's southern port city of Bushehr would start operating in the next few months.

In March, Iranian Energy Minister Parviz Fattah said the plant would generate around 500 megawatts by August 22, while Foreign Minister Manouchehr Mottaki announced that it would begin operating by September.

The Bushehr project has provoked fears in Western countries and Israel that it will give Iran nuclear expertise that could be used by the Islamic republic to develop a nuclear bomb.

But Russia has continued to pursue the project, which is being overseen by Atomstroiexport, part of state-owned Russian nuclear monopoly Rosatom.

Belenky also told Interfax that the Bushehr project had run into "financial problems" due to Russian banks that had declined to work with Iran.

"The problems with financing exist because not all Russian banks are ready to work with Iran, and we have to find alternative options. Due to this there are problems, but this is more a technical issue, and certainly not the fault of the Iranian side," he said.

The Bushehr project has experienced numerous delays, including some that were linked to problems in Iran's payments to Russia.

All rights reserved. � 2005 Agence France-Presse. Sections of the information displayed on this page (dispatches, photographs, logos) are protected by intellectual property rights owned by Agence France-Presse. As a consequence, you may not copy, reproduce, modify, transmit, publish, display or in any way commercially exploit any of the content of this section without the prior written consent of Agence France-Presse.