Sergei Kirienko, chief executive at Rosatom State Atomic Energy Corp., said talks with Iranian officials are close to completion.
"We hope that by the end of this year we will move on to the final signing and additions to the intergovernmental agreement, and then the according contract," he said Monday.
Russia supplies Iran with fuel needed to power its Bushehr nuclear reactor.
In March, a spokesman for the Atomic Energy Organization of Iran said the agreement calls for the pair of 1,000-megawatt reactors to be built near the first unit of the Bushehr nuclear power plant.
Russia is under pressure from a U.S. government frustrated with the Kremlin's reaction to Ukraine's move toward the European Union, while Iran is facing its own pressure from sanctions imposed for its controversial nuclear program.