Japan-US marine combat drills held amid fears over Chinese and Russian activity

An MV-22 Osprey participates during a joint military helicopter borne operation drill between Japan Ground Self-Defence Force and US Marines at Higashi Fuji range (AP)

Japanese and US marines have undergone their first airborne landing and combat training together near Mount Fuji as the two allies strengthen military cooperation amid growing maritime activity by China and Russia in the regional seas.

Japan has been expanding its defence budget and capability for about a decade and is now revising its key national security strategy in the face of threats from China, North Korea and now Russia.