June 24 (Bloomberg) -- A Japanese destroyer arrived in the southern Chinese port of Zhanjiang today to deliver earthquake-relief supplies, the first visit to China by a naval ship from Japan since World War II.

The ``Sazanami'' arrived in the Guangdong province port city for a planned five-day docking, Akio Takahashi of Japan's Defense Ministry said today. The 240-crew ship will host Chinese military officers and the Japanese sailors will play soccer and basketball games with their counterparts. The visit follows a Chinese navy missile destroyer's to Japan last year.

The military exchange comes amid improving ties between Asia's two largest economies after both agreed to try to set aside diplomatic controversies over Japan's occupation of parts of China in the 1930s and 1940s.

``This is a breakthrough that we've been looking for for a long time,'' said Phil Deans, a professor at Temple University in Tokyo specializing in Japan-China relations. ``These naval exchanges are really a way of trying to reassure the governments of both sides and reassure the people that they don't need to be worried about each other.''

Hu Jintao became the first Chinese president to visit Japan in a decade in May and last week the two countries reached an accord on joint gas exploration in the East China Sea, ending a four-year dispute. The deal is a breakthrough for Japanese Prime Minister Yasuo Fukuda, who has worked to improve relations that soured under former Premier Junichiro Koizumi.

Fukuda's Promise

Relations between China and Japan have warmed since 2006, when Fukuda's predecessor, Shinzo Abe, replaced Koizumi. Koizumi inflamed long-standing Chinese anger over Japan's conduct before and during World War II with trips to Tokyo's Yasukuni shrine, where war criminals are among those memorialized.

Japan's military is a sensitive issue around Asia, where millions died at the hands of the Japanese Imperial Army. Fukuda promised before becoming prime minister that he would not visit the war memorial, Yasukuni.

China's government has also worked to make the Chinese public's perception of Japan more positive. A Japanese rescue team was among the first foreign offers of rescue workers accepted by China after the May 12 earthquake in Sichuan province that killed more than 69,000 people.

The Sazanami is delivering supplies including 300 blankets and 2,600 items of emergency food.

Still, Japan has signaled unease with China's surging military spending. Japan's parliament authorized the use of outer space for defense purposes last month, supporting increased spending on rockets and satellites after China shot down a weather satellite in a military test last year.

Japan's defense ministry criticized that missile test, saying it threatened ``satellites around the world, whether they are civilian or military,'' according to its annual East Asian Strategic Review, published in March.

Hu promised during his May 6-10 visit to Japan his nation won't spark an arms race with its neighbors or pose a military threat to ``any country.''

To contact the reporter on this story: Dune Lawrence in Beijing at dlawrence6@bloomberg.net; Toko Sekiguchi in Tokyo at Tsekiguchi3@bloomberg.net.

Last Updated: June 24, 2008 04:24 EDT