TOKYO (AFP) - China's opaque spending on its huge and growing military is a "concern" for the world community, Japan said on Wednesday, after Beijing revealed another double digit budget hike.

"The transparency of China's defence policy and military capacity, or lack thereof, has become a matter of concern for the international community, including Japan," Chief Cabinet Secretary Yoshihide Suga told reporters.

The comments came after Beijing unveiled a 12.2 per cent rise in its 2014 budget for what is already the world's largest armed forces, as it seeks military clout in line with its new-found economic strength.

They also come after China lashed out at a five per cent rise in Japan's military budget over five years, which was approved late last year by the cabinet of hawkish Prime Minister Shinzo Abe.

"The Chinese defence budget for 2014 shows a double digit increase from the previous year," said Mr Suga.

"The government takes note of that, and we will continue to monitor the trend going forward.

"By co-operating with countries concerned and the international community, we will call on China to increase the transparency of its defence policy."

Mr Suga also offered a rebuttal to a barely-veiled criticism of Japan with the Chinese assertion that it would "safeguard the victory of World War II and the post-war international order, and will not allow anyone to reverse the course of history".

Japan will "absolutely never, ever reverse the course of history," he said.

"During the post-war period until today, we have walked on a path of freedom, peace and democracy. It is our path and our basic policy."