"The two ships left the Muroran port (in Hokkaido, northern Japan) this morning around 9:00 am (0000 GMT) as scheduled," said a spokesman for the Maritime Self-Defense Force.

"They will arrive in Kuwait in mid March," he said.

The dispatching of the Japanese naval vessels marks the first time Japan has deployed all three branches of the Self Defense Forces for overseas operations since they were established after World War II.

About 150 sailors were on the 8,900-ton Oosumi, while the 4,550-ton destroyer Murasame were carrying about 180 people, the official said.

Oosumi was carrying some 70 units of light armored vehicles, water-tank vehicles and trucks. It would also deliver construction materials and equipment for Japanese ground troops to offer humanitarian help in southern Iraq.

Around 100 Japanese ground troops are already in Samawa, 270 kilometres (168 miles) south of Baghdad, for a non-combat mission of offering humanitarian and reconstruction work in war-torn Iraq -- Japan's first dispatch of troops since World War II to a country where fighting is still under way.

A total of 600 ground troops will be in Iraq by the end of March, with logistical support from around 400 air force and naval personnel in the region.

Oosumi was sent previously for other humanitarian missions, including delivering aid materials for earthquake victims in Turkey in 1999 and carrying Japanese soldiers for UN peacekeeping operations in East Timor in 2002.

WAR.WIRE