Japan's cabinet has approved the country's largest defence budget, with plans to buy surveillance aircraft and F-35 fighter jets to improve defences of disputed islands amid China's increasing assertiveness in the region.

Prime Minister Shinzo Abe's Cabinet endorsed on Wednesday a nearly $42b defence budget for the year beginning in April, a two percent rise. The budget must still be approved by parliament, but Abe's coalition holds majorities in both houses.

The military outlays were included in a record $814b total budget for the coming fiscal year.

Japan's military budget is rising for a third year in a row under Abe, who took office in December 2012 and ended 11 straight years of defence budget cuts.

The increase mainly covers new equipment, including P-1 surveillance aircraft, F-35 fighter jets and amphibious vehicles for a new unit to boost island defences.

The 2015 budget also covers cost of purchasing parts of "Global Hawk" drones, planned for deployment in 2019, and two Aegis radar-equipped destroyers, as well as missile defence system development with Washington.

Chinese patrol boats often visit waters near uninhabited islands in the East China Sea, which are controlled by Japan but also claimed by China.

Abe favours a stronger role for Japan's military, despite a commitment to pacifism enshrined in the US-inspired constitution drawn up after the country's defeat in World War Two.

Japan's defence guidelines were revised in December 2013 as tensions rose over the disputed islands in the East China Sea.

In July, the Abe government adopted a new interpretation of Japan's war-renouncing constitution to allow its military to defend American and other foreign troops under attack.

Source: Agencies