Russian President Vladimir Putin proposed Wednesday that Russia and Japan sign a peace treaty by the end of the year without preconditions.
A treaty without preconditions would leave Russian Federation in control of the disputed islands, which Russian Federation calls the Southern Kuriles and Japan calls the Northern Territories.
"An idea has just come into my mind", Putin said at a regional economic forum in Vladivostok, which was also attended by Abe.
The top government spokesman also said Japan will not change its position of seeking to resolve the issue of the islands' sovereignty, before concluding the peace treaty with Russian Federation.
During a speech at the Easterm Economic Forum in Vladivostok, Russia, Chinese President Xi Jinping said Beijing's relationship with Russia is at an "all time high" as he called for further investments in Russia.
Later in the same session, Putin said of his offer: "I was not joking".
Fresh from his pancake diplomacy date with China's President Xi Jinping, Vladimir Putin served up the main dish on Wednesday - a possible breakthrough in Russian-Japanese relations.
President Xi highlighted that the two countries share common interests in many global issues, . and called for the need to cooperate more going forward.
President Vladimir Putin suggested Wednesday that Russian Federation and Japan sign a peace treaty this year, ending World War II hostilities "without any preconditions" as a territorial dispute has led to decades of deadlock. "We have been negotiating for 70 years", Mr Putin said.
FILE PHOTO: Japan Coast Guard vessel PS08 Kariba sails off Cape Nosappu, easternmost point in Japan, in Nemuro on Hokkaido island, as part of a group of islands known as the Northern Territories in Japan and the Southern Kuriles in Russian Federation can be seen in the background April 14, 2017.
The Japanese prime minister for his part said the two countries "have a duty to future generations".
A Japanese government spokesman said the country's stance had not changed. The Kuril Islands issue remains the sticking point since after WWII the islands were handed over to the Soviet Union while Japan has laid claims to the four southern islands. "Putin does not expect anything", Kunadze told the Echo of Moscow radio station.
Lying near the Japanese island of Hokkaido, the territory was taken over by Red Army troops in the final days of World War II.