Japan's defence ministry wants to develop its own early-warning aircraft, replacing US-made planes as the Chinese and Russian air forces grow more assertive, a report said Sunday.

The ministry has asked for an initial 80 million yen ($642,000) from the finance ministry for the next fiscal year starting April to produce a mock aircraft, the Yomiuri Shimbun reported.

It said that military planners want to complete the development programme for planes featuring advanced surveillance radar by the mid-2020s, to replace Japan's US-made E-2C Hawkeye planes, which are based on a 1960s design.

Japan says it scrambled fighter jets more than 800 times in the last fiscal year to shadow intruding aircraft, mostly from China and Russia. That was the highest number of deployments since the final year of the Cold War in 1989.

Fears of a military clash have heightened since China last November declared an "air defence identification zone" over the East China Sea, which overlaps a similar Japanese zone and covers territory disputed by the two countries.

Sunday's report comes after Japan lifted a self-imposed ban on weapons exports, as Prime Minister Shinzo Abe looks to expand the country's diplomatic and military reach after a long period of economic stagnation.

Defence ministry officials could not be reached to comment on the report.