Fennovoima has said it would choose this year between two potential suppliers, Areva (>> AREVA) and Toshiba (>> Toshiba Corp), but Rosatom on Saturday said Fennovoima had also recently opened talks with the Russian firm.
"That they contacted us came as a quite a surprise to Rosatom," Jukka Laaksonen, a vice president in Rusatom Overseas, Rosatom's export branch, said in a radio interview with national broadcaster YLE.
Laaksonen said it was possible that state-owned Rosatom could invest in Fennovoima's project, which it has estimated will cost around 4 to 6 billion euros.
Fennovoima declined to comment.
Last year's exit from the consortium of German utility E.ON (>> E.ON SE) raised doubts over plans to build the reactor in Pyhajoki.
Fennovoima's remaining owners, some 60 Finnish companies, this month said they would take on E.ON's stake of 34 percent, but there is still concern over the project's financing and know-how.
The proposed plant, the first reactor site announced after the disaster in Fukushima, Japan, is aimed at providing cheap energy to shareholders such as stainless steel maker Outokumpu (>> Outokumpu Oyj), retailer Kesko (>> Kesko Oyj) and subsidiaries of Swedish metals firm Boliden (>> Boliden AB). Production is due to start in the 2020s.
While other European countries are trying to phase out nuclear power, Finland is going ahead with its plans to build more in a bid to reduce carbon emissions and curb its dependence on electricity imports.
Finland's long, cold winters require high energy consumption and its forest and steel sectors rely on cheap and stable electricity.
(Reporting By Jussi Rosendahl; Editing by Rosalind Russell)