Russia says it has launched "unprecedented measures" to develop military infrastructure on the far eastern Kurile Islands where Moscow and Tokyo have rival territorial claims.

Colonel-General Sergei Surovikin, commander of the eastern military district, said in a May 27 statement that the measures include "a planned rearmament of the formations and units.”

Russia is taking the steps to "exclude the emergence of even the smallest risks," he added.

Surovikin also said Russia's navy sent six ships on an expedition to an island in the Kurile archipelago earlier this month to "study the possibility of future basing of Pacific Fleet forces there."

A dispute over the Kurile Islands, which Russia seized from Japan at the end of World War II, has strained ties and has kept the two countries from signing a peace treaty.

Based on reporting by AFP and Interfax

