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TOKYO, Dec 24 (Reuters) - Japan has supplied ammunition to South Korean troops serving in a U.N. peacekeeping mission in South Sudan, the Defence Ministry said on Tuesday, another step in Prime Minister Shinzo Abe's more assertive foreign policy.
It was the first time Japan's post-World War Two Self-Defence Forces (SDF) have provided ammunition to another country, the Defence Ministry said, and is the latest move to ease self-imposed constraints on its military.
Responding to a U.N. request, SDF engineering troops in South Sudan on the same operation supplied 10,000 rounds of ammunition to the South Koreans on Monday through the U.N. mission in South Sudan (UNMISS).
Abe returned to power a year ago for a second term pledging a tougher stand against China, with which Japan is locked in a bitter territorial dispute over East China Sea islets, and to bolster Japan's defence posture.
Relations between Tokyo and Seoul have also been strained by a separate territorial row and disputes over Japan's wartime history, including women - many Korean - who were forced to work in military brothels during World War Two.
Abe has raised Japan's defence spending for the first time in 11 years, set up the National Security Council to strengthen his grip on security policy, and laid out a new security strategy that calls for a review of Japan's decades-old ban on arms exports.
"Abe is working in small ways to erode the restrictions on exports. This fits his agenda to help transform larger economies of the Japanese defence industry," said Brad Glosserman, executive director at the Honolulu-based Pacific Forum CSIS.
He said the move was unlikely to signal a thaw in Japan's ties with South Korea. "It's a recognition that, in a bad situation where Korea needs help, it is smart to take help where you can get it," he said.
Chief Cabinet Secretary Yoshihide Suga said in a statement on Monday that the ammunition supply was exempt from the arms exports ban given its emergency and humanitarian nature.
The Japanese engineers are stationed in the South Sudan capital of Juba, while South Korean troops are in the rebel-held Jonglei State capital Bor, where the security situation is tougher.
"Ammunition that is in shortage is the same type as our country's troops have, and only our troops in the UNMISS mission have this type of ammunition in store," a Japanese government statement said.
"If we don't provide it for free, protection of the lives of the members of the South Korean troops and refugees are compromised," it said.
On Monday, U.N Secretary-General Ban Ki-moon asked the U.N. to send another 5,500 peacekeepers to South Sudan - almost double the existing force - as soon as possible to protect civilians from worsening violence that threatens to tip Africa's youngest country into civil war.
In 1967, Japan drew up "three principles" on arms exports, banning sales to countries with communist governments, those involved in international conflicts or those subject to United Nations sanctions.
The rules eventually became almost a blanket ban on arms exports and on the development and production of weapons, stifling Japanese defence contractors and making it difficult for them to keep up with cutting-edge arms technology. (Reporting by Kiyoshi Takenaka, Linda Sieg, Nobuhiro Kubo; Editing by Paul Tait)