Prime Minister Shinzo Abe led the LDP to a landslide election victory last month, promising to beef up the military and stand tough in the dispute over tiny, uninhabited islands, called Senkaku in Japan and Diaoyu in China.

The number of personnel, now standing at about 225,000, will increase by 287 in the next fiscal year starting in April, Onodera told reporters after meeting Finance Minister Taro Aso for the final budgetary negotiations.

Onodera said the increase was the biggest in two decades. The figure represents an expansion of about 0.1 percent.

"This would allow us to firmly reinforce our surveillance activities in the southwest," Onodera said.

The disputed islets are located to the southwest of Japan's main islands, where two countries share a maritime border.

Both China and Japan sought to cool down tensions in the row last week, with Chinese Communist Party chief Xi Jinping telling an envoy from Abe that he was committed to developing bilateral ties.

Onodera also said that the defence budget will grow 40 billion yen ($440 million), or about 0.8 percent, in the year from April, posting positive growth for the first time in 11 years.

A small budget rise had been expected as the LDP campaigned in December's lower house election on pledges to boost defence spending. The Defence Ministry this month requested an annual increase of about 100 billion yen in its budget.