FILE - In this Sept. 2, 2012 file photo, the survey ship Koyo Maru, left, chartered by Tokyo Metropolitan Government officials, sails around Minamikojima, foreground, Kitakojima, middle right, and Uotsuri, background, the tiny islands in the East China Sea, called Senkaku in Japanese and Diaoyu in Chinese. Japanese were voting Sunday, Dec. 16 in parliamentary elections that were expected to put the once-dominant conservatives back in power after a three-year break — and bring in a more nationalistic government amid tensions with big neighbor China. Japan's largest opposition Liberal Democratic Party leader Shinzo Abe in particular has taken a tough stance toward Beijing in the election campaign amid a simmering dispute over the islands in the East China Sea that are controlled by Japan but also claimed by China and Taiwan. (AP Photo/Kyodo News, File) JAPAN OUT, MANDATORY CREDIT, NO LICENSING IN CHINA, HONG KONG, JAPAN, SOUTH KOREA AND FRANCE

Japan is planning to develop a new tactical ballistic missile that would reset Chinese military strategy around disputed islands in the East China Sea.

Plans for the surface-to-ship weapon, which would be the longest-range missile ever built by Japan, have emerged after prolonged months of rancour between Tokyo and Beijing over rival territorial claims.

As tensions have persisted, Japan revealed last month that it scrambled fighter jets a record 199 times in the second quarter as Chinese military activities intensified around Japan’s territorial waters and drew closer to the uninhabited Senkaku islands — a chain known as the Diaoyu in China.

The new missile, say military experts familiar with the plans, is designed to “complicate enemy planning”. By positioning them on Japanese islands in the East China Sea and with a range that stretches to the edge of Japan’s territorial claims, the missiles would discourage naval aggression. If an attacking force were planning a landing on a Japanese island, its commander would need to destroy the missiles beforehand — in effect initiating conflict.

Japan’s move to build the missiles comes as the country strengthens its internal capability to develop military equipment after Prime Minister Shinzo Abe ended the country’s self-imposed ban on the export of weapons in 2014. The programme is part of a wider effort to reduce spending on foreign-made weaponry if a domestic alternative can be produced.

The new vehicle-mounted, GPS-guided missile system is expected to be deployed to locations such as the southern island of Miyako in Okinawa, according to people familiar with the plan.

With a range of about 300km, the system will be able to cover the waters around the Senkakus. Experts say the current Type 12 surface-to-ship missiles, which Japan procured in 2012, have a range of roughly 200km.

The defence ministry said it was studying ways to enhance its existing surface-to-ship missile capability to deter invasion of Japan’s remote islands.

But it declined to comment on details after an August 14 report in the Yomiuri Shimbun newsppaper said the new missiles were expected to be deployed around 2023.

Industry watchers say the move to develop a new missile is no surprise given that the ministry’s defence guidelines released in 2013 called for Japan’s Self Defence Forces to strengthen their ability to deal with attacks on islands using aircraft, naval vessels and missiles.

The ministry is currently explaining to local municipalities in Miyako and Ishigaki islands in Okinawa and Amami island of Kagoshima in southern Japan about its plan to deploy its surface-to-ship guided-missile units.

It is expected to seek funding for development of the new missile in its initial budget requests for the 2017-18 fiscal year, to be submitted later this month.

Governments in the Asia-Pacific region are closely scrutinising Japan’s military posture following this month’s appointment of Tomomi Inada as the country’s defence minister. The outspoken nationalist, who returned on Wednesday from a visit to a Japanese military base in Djibouti, has previously expressed a hardline position on Japan’s territorial rights in the East China Sea.