Japanese Prime Minister Shinzo Abe said Monday the signing of a Japan-Russia peace treaty, delayed for decades by a row over the sovereignty of a chain of islands, requires a “relationship of trust” between himself and Russian President Vladimir Putin, Nikkei reported.

“The peace treaty issue cannot be solved with just one leaders' summit, as shown by the fact it has gone unresolved for 70 years,” Abe said.

According to PM, concluding the treaty is “not an easy path,” reiterating that the contentious islands, seized from Japan by the Soviet Union at the end of World War II in 1945, fall under Russian sovereignty.

“There has been no change to our existing position on the Northern Territories,” he noted.

“We believe that it's of utmost importance that the future development (of the islands issues) be moved forward in a way that's a win-win,” Abe said.