MOSCOW, August 18. /TASS/. Japanese Ambassador to Moscow Akira Muto summoned to the Russian Foreign Ministry has arrived at the ministry on Tuesday, a TASS correspondent reports.

Answering a TASS question, Russian Foreign Minister Sergey Lavrov said earlier that the Japanese ambassador had been summoned to the Russian Foreign Ministry following Tokyo’s protest against President Vladimir Putin’s visit to the Kuril Island of Iturup. However, the Japanese embassy failed to clearly explain why its ambassador ignored a summons and said that the diplomat would not be able to come either on Friday, August 14, or on Monday, August 17. Russian Foreign Ministry Spokeswoman Maria Zakharova told TASS that Akira Muto "suddenly felt much better" after Lavrov’s words and would come to the ministry on August 18.

Russia and Japan have been negotiating a post-World War II peace treaty since the mid-20th century. The main stumbling block is the issue of who owns the South Kuril Islands. After the end of World War II, all Kuril Islands were incorporated into the Soviet Union. However, Japan claimed the Iturup, Kunashir, Shikotan islands and a number of uninhabited islands of the Lesser Kuril Ridge called the Habomai Islands in Japan as its own.

In 1956, the Soviet Union and Japan signed a joint declaration on ceasing the state of war. The two countries resumed diplomatic and other relations, but have still not signed a peace treaty.

The Russian Foreign Ministry has repeatedly said that Russia’s sovereignty over the Kuril Islands is not up for debate, as international agreements stipulate that they belong to Russia.