Russian Defense Minister Sergei Shoigu announced Friday that Moscow will deploy a range of missile systems on the Kuril islands, claimed by Japan, as part of its military buildup in the far-eastern region, Agence France-Presse reported. The islands have been a source of tense relations between Moscow and Tokyo.s 

"The planned rearmament of contingents and military bases on Kuril islands is underway. Already this year they will get Bal and Bastion coastal missile systems as well as new-generation Eleron-3 unmanned aerial vehicles," Shoigu said during a ministry meeting, AFP reported.

Russia has been investing in military infrastructure on the Kuril islands, which Japan considers its territory, leading to strained relations between the two nations. The status of the four southernmost islands in the Kuril chain, known in Japan as the Northern Territories, has been a matter of concern over the past few years.

Shoigu reportedly said at the meeting that the military is focusing on "developing military infrastructure in the Arctic and Kuril island zones."

The Russian navy's Pacific fleet has planned to begin a three-month mission to the Kurils next month to explore if the disputed islands could serve as a naval base as well.

Russia reportedly plans to build 350 structures for military needs on the Kuril islands of Iturup and Kunashir, called Etorofu and Kunashiri in Japan. The buildings will be put up this year and next year.

Nearly 19,000 Russians live on the islands, which were under Soviet occupation at the end of World War II. Russia and Japan never officially signed a peace treaty at the end of the war because of the dispute over the islands. It has also hampered trade ties between the two nations for decades.