Prime Minister Shinzo Abe has decided to visit Moscow in May to attend a ceremony marking the 75th anniversary of Russia's victory over Germany in World War II and hold talks with President Vladimir Putin, a Japanese government source said Friday.

Japan and Russia are trying to arrange a meeting between Abe and Putin on May 8 or May 10, according to the source. The ceremony will be held on May 9.

Abe will be the first Japanese leader to attend the ceremony since then Prime Minister Junichiro Koizumi in 2005.

Abe wants to break the stalemate in negotiations to conclude a postwar peace treaty with Russia through the envisaged summit with Putin. The previous meeting was held in September when Abe visited Vladivostok for an economic forum.

"The prime minister has been invited by Mr. Putin to attend the ceremony so it's a good opportunity to have dialogue between the leaders," a Japanese government official said. "There is no way (Abe) would turn it down."

Japanese Foreign Minister Toshimitsu Motegi and his Russian counterpart Sergey Lavrov are expected to meet on the fringes of a security conference in Germany in mid-February and lay the ground work for their leaders' meeting.

Close aides to Putin and Abe will also step up preparations for the summit, according to the source. Nikolai Patrushev, secretary of Russia's Security Council, is expected to visit Japan and meet with Shigeru Kitamura, who heads Japan's National Security Secretariat.

Despite rounds of negotiations, Japan and Russia have failed to bridge their differences over a long-standing territorial issue that has prevented them from signing a peace treaty.

Tokyo maintains that Moscow illegally seized the four islands called the Northern Territories in Japan and the Southern Kurils in Russia. Russia claims that the seizure was legitimate following Japan's 1945 surrender in World War II.

In November 2018, Abe and Putin agreed to advance negotiations based on a 1956 joint declaration, stating that Shikotan and the Habomai islet group will be handed over to Japan following the conclusion of a peace treaty. The remaining two are Etorofu and Kunashiri.

Arrangements had been made for Abe and Putin to meet on the occasion of an Asia-Pacific Economic Cooperation forum in Chile in November. But Putin decided not to attend the gathering, which Chile later canceled due to violent protests.

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