A top Iranian nuclear official on Thursday produced a slew of figures to angrily deny Russian charges Tehran had not paid a cent towards the construction of its first nuclear power plant since January.

"Probably, the officials from the Russian federal energy agency do not have sufficient financial information," the deputy head of Iran's atomic energy organisation Mohammad Saeedi told the IRNA agency.

Russian contractor Atomstroiexport has been building Iran's first nuclear power plant in the southern city of Bushehr but earlier this month announced the latest delay in what has been a long and troubled saga.

Sergei Kiriyenko, chief of Russia's federal nuclear energy agency, on Wednesday said Iran appeared to have "lost interest" in completing the plant, adding that it had handed over no payments since mid-January.

"Between October 10 and December 12, we paid 58 million dollars and from January 1 to 31 we paid 16.9 million dollars to the Russian side," said Saeedi.

"In February we also paid the sum of 56 billion rials, in other words 6.2 million dollars."

Saeedi also took issue with Kiriyenko's language, after the Russian official said that Tehran had had not paid a "single kopek" since mid-January.

He said it was surprising that Kiriyenko spoke in terms of the kopek -- Russia's lowest currency unit -- "when for the past 11 years all the Iranian payments have been made in dollars or in euros."

Iran has repeatedly denied it is behind on payments and hinted that political pressure from the United States could be behind Russia's delays in finishing the project.