High-level brass from the Self-Defense Forces and the Russian military agreed to continue defense exchanges in a series of meetings in mid-December, according to Japanese government sources.

The meetings were held to prevent accidental collisions or other emergencies from occurring around Japanese airspace, given the 2.4-fold surge in scrambles conducted by the Air Self-Defense Force to intercept Russian planes in the April-September period amid strained ties caused by the Moscow's interference in Ukraine, the sources said Friday. The ASDF has conducted at least 324 scrambles in response to Russian planes.

According to the sources, on Dec. 16 last year the chief of the ASDF's Northern Air Defense Force went to the Russian city of Khabarovsk to meet the head of the air and air defense forces tasked with Russia's Eastern Military District.

From Dec. 18 to 19 in Tokyo, Japanese and Russian foreign and defense officials held their annual consultation on a Japan-Russia accord signed in 1993 to prevent incidents from occurring between their aircraft and ships.

At both of these meetings, the officials agreed to continue defense exchanges to prevent unnecessary friction.

In response to tensions over Ukraine, Tokyo maintains the position that it will cooperate with the Group of Seven major nations to seek a resolution to the crisis. After Russia's annexation of Ukraine's Crimea region in March, Japan joined the United States and European nations in imposing sanctions on Moscow.

Efforts to mend Japan-Russia ties through defense cooperation included joint naval search and rescue exercises in October last year by the Maritime Self-Defense Force and the Russian Navy.