Russia's state-run nuclear energy firm Rosatom said on Monday it is suing Finnish company Fennovoima for about $3 billion.
"To date, Rosatom already filed six lawsuits totaling $3 billion. The details of the claims are confidential and are not subject to disclosure," Rosatom's press service said in a statement.
Earlier, Joachim Specht, CEO of Fennovoima, said in an interview with a Finnish newspaper that his firm filed a lawsuit for €2 billion ($1.9 billion) against Rosatom.
In May, Fennovoima announced the termination of the contract with the Finnish branch of Rosatom, citing delays in the fulfillment of obligations on the Russian side.
The Russian firm was given the contract for the construction of the Hanhikivi-1 nuclear power plant in Finland.
In response, Rosatom said the company was strictly fulfilling all its obligations on its international projects.
Rosatom claimed the Finnish side terminated the contract without discussion with shareholders.