The government is lobbying Japanese firms to invest in Russian projects to help secure a breakthrough in a festering territorial row with Moscow when President Vladimir Putin visits Japan in December, sources have said.

The dispute over three islands and a set of islets off east ern Hokkaido, called the Northern Territories in Japan and the Southern Kurils in Russia, has kept Tokyo and Moscow from signing a peace treaty formally ending their conflict in World War II.

Prime Minister Shinzo Abe is betting his close ties with Putin and the lure of investment from Japanese companies could set the stage for progress in the dispute when the pair meet in Abe's home constituency, Yamaguchi, on Dec. 15.