The first plane arrived around 11:30 am (0830 GMT) and was followed some 30 minutes later by the two others.

The aircraft brought in 40 flight crew and maintenance personnel, air force spokesman Captain Kazutoshi Ohmura told reporters at the base, 60 kilometres (37 miles) west of Kuwait City.

Sixteen Japanese air force personnel were seen disembarking the first plane and were received by the Japanese ambassador to Kuwait, Sumio Tarui, as well as Japanese military officers and diplomats.

The latest arrivals bring to around 200 the number of Japanese air force personnel in Kuwait, including a small advance party that arrived here at the end of December, in preparation to support troops performing humanitarian aid missions in neighbouring southern Iraq.

Asked when the mission would start, Ohmura said: "We need exercises and to get prepared."

He said training would be carried out with US forces in the emirate and would include flight exercises and maintenance.

"We recognise the danger of this mission but we are prepared how to land (the planes) and take off," Ohmura said. "Our planes are equipped ... for protection from surface-to-air missiles."

The ambassador said the Japanese air force personnel "will all be engaged in transporting humanitarian aid from Kuwait to Iraqi cities. This is the main task of the Japanese self-defence forces.

"Maybe they will be able to start (towards) the end of next month, but this depends on conditions" related to the exercises, Tamui told reporters.

Japan on Monday ordered the dispatch of some 600 troops to provide humanitarian and reconstruction aid to Iraq, in what will be its first full deployment to a combat zone since World War II.

The Japanese government announced its plan to assist with providing clean water and reconstruction in the southern Iraqi town of Samawa in December, but the green light was conditional on a small advance party of soldiers reporting that it was safe for the troops.

US-led coalition troops have been fatally targetted amid the raging insurgency in Iraq.

The first Japanese soldiers will leave home around February 3, Jiji Press agency has reported, and all 600 should be in place by the end of March, with logistic support from around 400 airforce and naval personnel in the region.

WAR.WIRE