Moscow (ANTARA News/AFP) - The war of words between Russia and Japan escalated on Monday when Moscow called Tokyo`s latest comments on a disputed island chain "clearly undiplomatic".

Prime Minister Naoto Kan used a national remembrance day Monday to call President Dmitry Medvedev`s November visit to the Kuril Islands -- which are known as the Northern Territories in Japan -- an "unforgivable outrage".

Russia`s response was swift, with Foreign Minister Sergei Lavrov calling the comments hostile and accusing Tokyo of pandering to Japanese nationalists.

"These expressions are clearly undiplomatic," Lavrov said during a joint press conference with his visiting Hungarian counterpart Janos Martonyi.

"They contrast sharply with the respectful, positive tone that was characteristic of the meeting between Prime Minister Naoto Kan and President Dmitry Medvedev in Yokohama last autumn," Russia`s top diplomat said.

Kan`s remarks came on Northern Territories Day -- which marks the conclusion of an 1855 treaty with Russia that Tokyo says confirmed that the four islands are Japanese territory.

The windswept chain was claimed by the Soviet army in 1945 and has since remained a point of contention that has soured trade ties and prevented the signing of a formal treaty ending World War II.

Medvedev`s unprecedented trip to one of the islands was followed by a series of trips to the chain by other Russian officials including last week`s visit by Defence Minister Anatoly Serdyukov.

Lavrov accused the Japanese government of supporting the country`s nationalist organisations who he said behave "in absolutely unacceptable terms".

"What is especially sad and regrettable is that the Japanese government not only finances these non-governmental organisations, but has also in the past year increased such financing," he said.

At the same time, Lavrov stressed that Russia wanted broader economic and diplomatic relations with Japan -- a position underscored in the past few days by both countries` leaders.

"We are still ready, as we have said on many occasions before, to cooperate in the closest manner possible with our Japanese neighbours in the implementation of specific projects in this region," said Lavrov.(*)

Editor: Aditia Maruli Radja
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