Iran and Russia have discussed a draft agreement to build at least two nuclear power stations in the Islamic Republic, Iran's official news agency reported.

Visiting Russian official Nikolai Spassky and Iranian nuclear officials reached an initial agreement on Wednesday about the facilities, IRNA said.

"Iran and Russia reached a preliminary agreement to build at least two new nuclear power plants," Iranian Atomic Energy Organisation spokesman Behrouz Kamalvandi told the news agency.

The two new 1,000 megawatt plants will be constructed alongside the existing power station in Bushehr, which was also built by Russia, Kamalvandi said.

Further talks will be held on technical and financial aspects of the project, but a final agreement is expected to be signed "very soon", he added.

The Bushehr facility has been running since 2011 with a capacity of 1,000 megawatts.

Iran, which still faces tight Western sanctions on its oil and banking sectors despite a landmark agreement reached with major powers in November on its nuclear programme, is expected to fund the new Bushehr project on a barter basis.

Tehran's ambassador to Russia, Mehdi Sanaei, said last month that the close trading partners have been negotiating the delivery by Iran of hundreds of thousands of barrels of oil per day in return for Russian goods and services, including the planned new nuclear plants.