TOKYO - Japan lodged a "stern" protest with Russia Wednesday over military exercises that are being held on the disputed Kuril islands, the Japanese foreign ministry said.
Moscow launched drills Tuesday on the long-contested islands, which are located off Russia's far eastern coast and just north of Japan.
The exercises are "extremely regrettable," said a foreign ministry spokesman.
"We have filed a stern protest with the Russian embassy," he added.
Responding to questions about the drills, Japanese Prime Minister Shinzo Abe told reporters earlier in the day that "our country, for its part, can't accept this at all".
The exercises came after Russia scrapped a meeting with a Japanese minister in response to a new round of sanctions by Tokyo against senior figures involved in the annexation of Ukraine's Crimean peninsula.
The meeting, originally scheduled for late August, was expected to focus on the simmering territorial dispute.
Soviet troops seized the islands just after Japan surrendered in World War II, with the long-standing dispute hampering trade and keeping Moscow and Tokyo from signing a post-war peace treaty.
Both the Kremlin and Abe had hoped to start mending relations in order to revive trade, with Japan seeking broader access to Russia's plentiful oil and natural gas supplies.
Russian President Vladimir Putin hosted Abe in April 2013 for the two sides' first formal summit in Moscow in a decade.
The leaders agreed to set in motion a series of high-level talks about Tokyo's claim to the southern Kuril chain that it still refers to as the Northern Territories.