President Vladimir Putin suggested Wednesday that Russia 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.
But Putin's sudden proposal was received cooly in Japan, where a government spokesman said the two countries should first resolve the dispute before signing a peace deal.
The dispute between Russia and Japan centres on four islands in the strategically-located Kuril chain which the Soviet Union occupied at the end of war in 1945 but are claimed by Japan.
It has kept the two countries from signing a peace accord that would formally end their wartime hostilities.
"We have been trying to solve the territorial dispute for 70 years. We've been holding talks for 70 years," Putin said at an economic forum in the far eastern Russian city of Vladivostok attended by Japanese Prime Minister Shinzo Abe and Chinese leader Xi Jinping.
"Shinzo said: 'let's change our approaches.' Let's! Let's conclude a peace agreement, not now but by year's end without any preconditions," Putin said, prompting the audience to break into applause.
- 'Not a joke' -
"It is not a joke," Putin added, suggesting the two countries commit to solving the territorial dispute in the text of the peace deal.
Putin said the conclusion of such a deal would create a better atmosphere and allow Russia and Japan to "continue to solve all outstanding issues like friends."
"It seems to me that this would facilitate the solution of all problems which we have not been able to solve during the past 70 years."
The Japanese prime minister said the two countries "have a duty to future generations."
"Let us walk together mindful of the questions, 'If we don't do it now, then when?' And 'if we don't do it, then who will?'," Abe said, speaking before Putin. "We are both fully aware that it will not be easy."
Kremlin spokesman Dmitry Peskov, speaking to reporters, described Putin's proposal as an impromptu idea and said the two leaders had not yet discussed it.
"Putin intends to solve this problem," he added.
A Japanese government spokesman said the country's stance had not changed.
Japan's Chief Cabinet Secretary Yoshihide Suga said a treaty with Russia would be signed "after resolving the issue of the attribution of the Four Northern Islands," referring to the disputed territory.
On Monday, Putin had seemed to pour cold water on suggestions that the dispute could be solved soon.
"It would be naive to think that it can be solved quickly," Putin said after meeting Abe on the sidelines of the forum.
- 'Putin trolls Abe' -
Some diplomats said Putin's proposal was a non-starter.
A former Russian deputy foreign minister, Georgy Kunadze, said he doubted Putin wanted to solve the territorial problem in earnest.
"This is called trolling. Putin does not expect anything," Kunadze told the Echo of Moscow radio station.
He suggested Abe would never accept a deal that would be political suicide.
Alexander Gabuev, head of the Russia in the Asia Pacific Program at the Carnegie Moscow Center, suggested Putin's proposal was a sign of frustration at a dearth of Japanese investment.
"This appears to be just emotions and an attempt to put pressure rather than anything real," he told AFP.
Putin and Abe have held numerous meetings over the past few years in a bid to solve the dispute over the islands.
The two countries have launched various economic projects on the islands in areas such as the farming of fish and shellfish, wind-generated energy, and tourism.
Russia's deputy foreign minister Igor Morgulov told Russian news agencies that Putin's announcement would not require any changes to the current format of negotiations.
The Kurils, which lie north of Japan's Hokkaido island, have been controlled by Moscow since they were seized by Soviet troops in the dying days of World War II.
The four islands whose population stands at some 20,000 people are known in Russian as Iturup, Shikotan, Habomai and Kunashir.
Putin's predecessor, Dmitry Medvedev travelled to Kunashir in 2010, becoming the first Russian leader to visit the disputed islands and provoking fury in Tokyo.