Japan moved closer to sending troops to Iraq with Prime Minister Junichiro Koizumi approving a deployment schedule. The troops are expected to start preparing Friday for a humanitarian mission to Iraq. Mr. Koizumi endorsed a plan Thursday to mobilize Japanese troops for duty in Iraq, the nation's first deployment to a combat zone since World War II.

Shigeru Ishiba, the head of Japan's defense agency, said he would issue an order Friday for the troops to begin preparing for a deployment that is expected to take place early next year. Japanese media reports say some advance contingents could be sent out in the next few weeks.

Up to 1,000 Japanese military personnel will be part of the deployment - falling far short of what Washington would like from its key Asian ally. The United States is in charge of the reconstruction efforts in Iraq and is counting on its allies for support. Japan has already pledged $5 billion for the rebuilding effort.

The Japanese troops are expected to be deployed in southeastern Iraq, where they will perform non-combat construction work. Japan's pacifist constitution limits its military to a self-defense role. But Parliament passed a law earlier this year authorizing the dispatch of non-combat troops to Iraq. The troops will carry weapons to use if they are attacked.

The plan is highly controversial in Japan and most people say they disagree with it. Government spokesman Yasuo Fukuda tried to calm public tensions Thursday. He says security in Iraq will lead to security in the Middle East and to security in international society. He adds that the Iraqi people have suffered in the past so Japan wants to help them and improve conditions there.

But many people fear that troops could come under fire or that terrorists could strike Japan, as they have threatened to do. The fatal shooting of two Japanese diplomats in Iraq last month escalated concerns and drew strong criticism from newspapers and opposition politicians.