Japan will raise military spending this year for the first time in over a decade under a ruling party plan, an official said Tuesday, as Tokyo summoned Beijing's envoy in a territorial row.

The national defence task force of the newly-elected Liberal Democratic Party will increase the defence budget request by more than 100 billion yen ($1.15 billion) in response to an emboldened China, a party official told AFP.

The relatively small amount -- just over two percent of the total military budget -- is largely symbolic, but reflects anxiety at what Japan sees as an increasingly hostile region in which China appears happy to throw its weight about.

"We have decided that the additional budget will be used for research into a new radar system as well as fuel and other maintenance costs for early-warning aircraft," the official said on condition of anonymity.

The news came as the foreign ministry called in China's ambassador to protest at the latest dispatch of official vessels into waters around the Tokyo-controlled Senkaku islands, which Beijing claims as the Diaoyus.

The summons was the first under nationalistic Prime Minister Shinzo Abe, and is in line with the tough stance he pushed on China on the campaign trail in December.

Beijing, however, rebuffed the move. Hong Lei, spokesman for China's foreign ministry, told reporters in Beijing patrols were "normal" because the islands are Chinese territory.

Nerves in Tokyo have also been rattled by an unpredictable North Korea. It sent a rocket over Japan's southern islands last month in what it insisted was a satellite launch. Tokyo and its allies said the launch was a covert ballistic missile test.

The military is bound by the country's US-imposed pacifist constitution, which restricts its ability to project power or to wage aggressive war. However, commentators say it is a modern, well-funded and well-equipped force.

In the run-up to last month's election, the LDP pledged to expand the number of personnel in the Self-Defence Forces and boost their equipment and spending power.

The proposed increase in funding comes after declines over 10 consecutive years as Tokyo grappled with its huge public debt.

The initial defence budget for fiscal 2012, which ends in March, stood at 4.65 trillion yen. This compares with a budget for fiscal 2002 that peaked at 4.94 trillion yen.

Defence Minister Itsunori Onodera has said Abe's government will review Japan's long-term basic defence programme, adopted in 2010 under the Democratic Party of Japan which was routed at the polls.

The current programme includes plans to trim troop numbers by around 1,000.

Kazuhiko Togo, director at the Institute for World Affairs of Kyoto Sangyo University, said the planned rise in defence spending was a direct result of China's more hostile attitude, specifically over the disputed islands.

"China has publicly said it would seize the islands by force if necessary and acted as such. To avoid a possible armed clash, Japan has no choice but to possess deterrence by boosting its defence budget," he said.

Hitoshi Tanaka, former diplomat and chairman of the Institute for International Strategy at the Japan Research Institute said at around 0.9 percent of GDP, Japan's defence budget was comparatively small.

"Given the fact that there is a rather difficult security environment these days, it is only natural for the government to think about increasing this," he said.

Abe has pledged to improve ties with key ally the United States and other democracies in the region, including Australia and India, as a counterbalance to China.

The United States stations some 47,000 troops in Japan as part of an alliance that enjoys broad support among political leaders, but is sometimes unpopular in communities that host bases, particularly on Okinawa.

A rise in defence spending will likely be welcomed in Washington, which has called for Tokyo to shoulder more of the burden of regional security.

However, any attempt to reinforce Japan's military has traditionally aroused suspicion in countries like China and the two Koreas, which fell victim to its wartime rampage.