Russian President Vladimir Putin has proposed signing a World War II peace treaty with Japan by the end of the year "without preconditions."
Putin made the surprise offer in public, sitting next to Japanese Prime Minister Shinzo Abe on a stage at an economic forum in the Russian city of Vladivostok on September 12.
After Abe pressed Putin on the subject of a treaty and a solution to the decades-long dispute over a group of islands claimed by both countries, Putin said: "An idea has just come into my head."
"Shinzo said, 'Let's change our approaches.' Let's! Let's conclude a peace agreement -- not now but by the end of the year, without any preconditions," Putin said.
He said issues that are in dispute could be resolved later, and that the pact could specify that the sides are determined to reach mutually acceptable agreements.
There was no immediate response from Abe, whose country has sought the return of the islands that lie northeast of Hokkaido since the war.
A treaty without preconditions would leave Russia in control of the disputed islands, which Russia calls the Southern Kuriles and Japan calls the Northern Territories.
Soviet forces occupied the islands at the end of World War II, and the territorial dispute has prevented Moscow and Tokyo from formally ending hostilities in the war.
Russian and Japanese Foreign Ministry officials said that work on a future agreement would continue as usual, and a Japanese official made clear that Tokyo wants an agreement on possession of the islands before it will sign a peace treaty.
"The government will continue its negotiations on the basic principle that we will sign a peace treaty after resolving the issue of the attribution of the four Northern Islands," Chief Cabinet Secretary Yoshihide Suga told reporters. "This stance hasn't changed."
In Moscow, Deputy Foreign Minister Igor Morgulov told Russian news agencies that Putin's announcement would not require any changes to the current format of negotiations.
Kremlin spokesman Dmitry Peskov said later in the day that Putin and Abe had not had a chance to discuss the proposal.
Russian commentator Georgy Kunadze, a former deputy foreign minister, told Ekho Moskvy radio that he believes Putin was "trolling" Abe and "does not expect anything" to result from the proposal.
The quest for the return of the islands is an emotive issue in Japan, and Kunadze suggested that Abe would never accept a deal that would be political suicide.
In years of talks, Russian officials have repeatedly signaled that Japan could not hope for a swift solution and hinted that the best way to get closer to a deal was to invest in the sparsely populated, windswept islands and engage in other areas of economic cooperation.
Meeting Abe on the sidelines of the forum in Vladivostok two days earlier, Putin had told the Japanese prime minister that "it would be naive to think that it can be resolved quickly."
In his remarks on September 12, Putin said concluding a pact would create a better atmosphere and enable Russia and Japan to "continue to resolve 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 over the past 70 years."