Russia plans to build a military base on the Kuril islands, a group of Pacific islands it seized from Japan at the end of World War Two, Defence Minister Sergei Shoigu said on Thursday, according to the Interfax news agency.

The move is likely to worsen already frayed relations with Tokyo which lays claim to the Southern Kuril, known in Japan as the Northern Territories.

The dispute is so acrimonious that Moscow and Tokyo have still not signed a formal peace treaty after the war.

Russia is also building or plans to build a series of new Arctic military bases, including on Wrangel Island, Kotelny Island and at Cape Schmidt, Russian Defence Minister Sergei Shoigu was quoted as saying on Thursday by the Interfax news agency.

"We are not keeping this a secret - we have practically created a base on the Novosibirsk Islands, the Island of Kotelny. This is a big military base, there was no such in the Soviet period," it quoted Shoigu as saying.

(Reporting by Jack Stubbs; Editing by Andrew Osborn)