(CNN)On Tuesday, the leaders of Japan and Russia will hold talks on what remains one of the world's longest-running unresolved international disputes.
The Kuril Islands, referred to as the Southern Kurils by Russia and the Northern Territories by Japan, were captured by Soviet forces following Japan's surrender to Allied Forces in 1945.
The resulting disagreement over who has rightful ownership of the islands has soured relations between the two countries, contributing to their continued failure to sign a World War II peace treaty.
The disputed territory, located off the coast of the Japanese island of Hokkaido, consists of four separate islands: Iturup, known in Japanese as Etorofu, Kunashir, or Kunashiri, Shikotan and the islet group of Habomai.
The two governments are pushing for a treaty to be signed based on a 1956 declaration, which acknowledged the cessation of WWII hostilities but did not set out terms for a formal peace agreement.
Japanese media states that the terms of the 1956 accord would hand over Shikotan and the Habomai islands to Japan, a sensitive notion inside Russia, where the ceding of any territory to Japan would likely be met by protests.
'This is Russia's territory'
The territorial dispute was raised ahead of Prime Minister Shinzo Abe's trip to Moscow this week to meet with Russian leader Vladimir Putin.
However, Sergey Lavrov, Russia's top diplomat, has downplayed the chance of the island chain returning to Japan. When Lavrov and Japanese Foreign Minister Taro Kono met last week in Moscow, the Russian told his Japanese counterpart that "sovereignty over the islands was non-negotiable," according to Russian state media. "This is Russia's territory."
A handful of Russian nationalists took to Moscow's streets Sunday, demanding that the government stand firm on the issue, chanting "(The) Kurils are Russian land!"
Igor Skurlatov, a speaker at the rally, which was estimated at around 500 people strong by the city's security department, called any suggestion to hand over the territory an act of treason.
The unequivocal language comes following Russian dismay with Tokyo's recent statements on the island group's status, with Kono sta