Japan’s government said two Russian fighter jets entered the country’s airspace Thursday, prompting Tokyo to respond by scrambling its own aircraft near the northern island of Hokkaido.

Moscow denied that its aircraft crossed into Japanese territory, saying its pilots were conducting a routine flight mission near the Russia-Japan border.

"Flights by the air force of the Pacific Fleet take place regularly in this region, in strict adherence to ... international rules, without violation of state borders," Roman Martov, Russian military spokesperson, said in a statement, Al-Jazeera reported.

The alleged incident occurred on the same day during which the Japanese government reaffirmed its claims on a set of disputed islands north of Hokkaido known as the Northern Territories in Japan and the Southern Kurils in Russia.

The Russian aircraft had reportedly flown over the disputed islands, which Moscow claims were handed over to Russia at the end of World War II.

As a result of the territorial dispute, Japan and Russia have not signed a peace treaty, formally ending the war.

Japanese Prime Minister Shinzo Abe said Thursday he was seeking a solution to the dispute with Russia during a speech to mark “Northern Territories Day.”

"In the telephone talks, I told [Russian] President [Vladimir] Putin I would make efforts to find a mutually acceptable solution so as to ultimately solve the issue of the Northern Territories," he said, the BBC reported.

"The Japanese government will continue to pursue the settlement of the territorial issues with a strong will,” Abe said in additional comments, according to Russia Today. “We aim to finally resolve the problem with Russia on the disputed islands, which will finally determine the ownership of the islands and realize the signing of a peace treaty."

Moscow has indicated that it is willing to jointly develop resources in waters around the islands, which may contain vast oil and natural gas reserves and are used for commercial fishing, though Japan has been adamant that it wants full ownership of the islands.

In 1904-1905, Russia and Japan, both imperial powers, fought a war over their ambitions in Korea and Manchuria. The Japanese won what is considered the first “great war” of the 20th century.