Russian claim to tiny islands infuriates Japan

A long-running diplomatic dispute between Japan and Russia over a chain of islands in the western Pacific escalated yesterday, with the Japanese Prime Minister branding a recent visit to the disputed territory by Russian President Dmitry Medvedev "an unforgivable outrage".

Naoto Kan was speaking at a large, government-organised rally in Tokyo, held every year in support of Japan's claim to the four southernmost islands in the Kuril chain. The islands are part of a volcanic archipelago that stretches around 800 miles from Russia's far-eastern Kamchatka Peninsula all the way to the tip of Hokkaido, Japan's northern island.

The islands have swapped hands between Russia and Japan over the years, and were seized by Russia at the end of the Second World War. Disagreement over the islands meant the two countries never signed a formal peace treaty after the war. Yesterday was "Northern Territories Day" in Japan, which marks the date of an 1855 treaty that the government says proves the country's claim to the islands.

Public opinion in Japan is driven by the descendants of former residents of the islands, who say they want to return. Loudspeaker vans adorned with slogans were driven to the Russian Embassy in Tokyo yesterday, as protesters waved flags and chanted. The Russian Foreign Minister, Sergey Lavrov, said that the protesters had defaced a Russian flag and branded their actions as "unacceptable".

Russia says that these Far Eastern outposts are non-negotiable sovereign territory, and Mr Lavrov yesterday accused Mr Kan of "undiplomatic" statements. The Japanese Prime Minister was protesting over a November trip to the Kurils by Mr Medvedev, the first visit by a Russian or Soviet leader. Last week the Russian Defence Minister, Anatoly Serdyukov, toured military garrisons on the islands and promised that Moscow would upgrade them.

Tokyo was furious over both trips, but Russia has also beefed up its rhetoric. After Mr Medvedev's controversial visit, he said that the islands were part of Russia's sovereign territory and he would return there whenever he wanted to. The islands are sparsely populated, but they are surrounded by excellent fishing waters and possible offshore oil and gas deposits. One of the disputed islands is visible on a clear day from the northernmost tip of Japan.

Sergey Prikhodko, a top Kremlin foreign policy aide, said yesterday that the sovereignty of the Kurils was not up for discussion "today nor tomorrow". He added that Mr Medvedev did not need anybody's permission to visit any part of his own country. "He [Mr Kan] should get ready for a difficult period," said Mr Prikhodko, commenting on the Japanese Prime Minister's criticism of Mr Medvedev's visit. "What the Japanese see as supposed insults, and what we see as working visits of the head of the Russian state, will absolutely continue to take place."

Japan's Foreign Minister arrives in Moscow on Thursday, and the islands will be the main topic of discussion. After yesterday's exchanges, the talks will be difficult, and few expect any major progress in the dispute. Nevertheless, it is unlikely that the spat will be allowed to ruin growing economic ties between the two countries.