Russia’s Foreign Minister Sergey Lavrov has blasted persisting US military buildup in Japan, saying Moscow views as a direct "threat" the American missile defense systems deployed to the Asian country.

The Russian top diplomat made the remarks following a meeting in Moscow with his visiting Japanese counterpart Taro Kono on Friday.

“We�ve yet again drew attention to certain actions of Washington, including the deployment of the global missile defense systems’ elements to Japan, bolstering of its military presence in the region and activities in the arms control sphere, where the US is demolishing all the existing agreements,” Lavrov said. “We perceive such actions as a threat for our country.”

Russia has in the past argued that the missile systems can double function as attack weapons and fire nuclear-tipped missiles at Russian targets. Moscow also fears that Washington would use the system�s powerful radars to gather intelligence from Russian territories.

Russian Foreign Minister Sergei Lavrov (R) and his Japanese counterpart Taro Kono attend a news conference after their meeting in Moscow on May 10, 2019. (Photo by AFP)

The high-profile meeting came as Russia-Japan bilateral ties face several challenges, including major disagreements over signing a formal peace treaty after the end of World War II.

Moscow and Tokyo never signed an official peace treaty following the war, leaving Japan with unresolved territorial claims on four Russian Kuril Islands. Back then, the islands of Iturup, Kunashir, Shikotan, and Habomai – known in Japan as the ‘Northern Territories’ – were handed over to the former Soviet Union under the 1945 Potsdam Declaration.

Russian President Vladimir Putin and Japanese Prime Minister Shinzo Abe agreed last year to resume discussions of a peace treaty -- based on the 1956 declaration signed the former USSR and Japan -- that envisioned potential handing over of island of Shikotan and islets of Habomai to Japan.

According to the 2018 discussions, any territorial exchanges would only be possible after inking a peace treaty. Tokyo, however, insists on first solving the territorial dispute, preferably with Moscow handing over all the disputed territories.

Arleigh Burke-class guided missile destroyer USS John S. McCain is seen at Fleet Activities Yokosuka, Japan. (File photo by Reuters)

“The joint declaration was adopted under particular historical and geopolitical circumstances. Since then, the situation has changed drastically. We have to consider the active security treaty between Japan and the US,” Lavrov explained after his meeting with Kono on Friday.

He further pointed out that despite the outstanding “differences,” Moscow want to resume negotiations. However, he added, any agreement must “fully reflect interests of our two countries and should be unambiguously accepted by the two nations.”

“Such task is not an easy one. Obviously it can be achieved only through continuous, meticulous and creative work,” the top Russian diplomat also underlined.