KIGALI, Rwanda (AP) _ The Rwandan Hutu refugees aid workers are desperately trying to feed are the victims _ but also a cause _ of war in eastern Zaire.

During the two years the refugees have refused to return home, nearly $1 billion of aid has streamed in _ aid that has saved lives but also fueled ethnic and political war.

Strengthened by humanitarian aid, Hutu fighters used the U.N. refugee camps to launch armed incursions into Rwanda. When Zairians began a rebellion, the Hutu fighters joined the Zairian army.

Foreign donors gave food and medicine but failed to find a political solution that would close the camps _ inadvertently helping the region deteriorate into a series of small wars.

``Most aid does not work. It is a waste of sympathy,'' says Alex de Waal, of London-based African Rights. ``Let's have less of it until we can ensure its quality and ethics.''

A U.N. agreement with rebels, announced today, is expected to speed delivery of food and medical aid _ at least to Goma residents.

But the rebels' hold on the territory came under threat today as heavy artillery was fired into Goma from seven miles northwest, where Rwandan Hutu militia are believed camped.

It remains uncertain how much-needed food and medicine will reach as many as 700,000 Rwandan Hutu refugees who fled their established camps when fighting broke out three weeks ago between the rebels and the Zairian army.

Canada has agreed to lead a U.N. military contingent that could bring up to 20,000 troops to try to restore calm and aid more than 1 million Rwandan refugees.

U.N. Secretary-General Boutros Boutros-Ghali hinted Tuesday the task force could become involved in trying to root out Hutu militiamen from among the refugees.

Rebel commander Andre Ngundu Kissasse said today his group welcomed Canada's offer, but reiterated that French participation was unacceptable. France drew criticism when it intervened during the Rwanda crisis in 1994. Kissasse said his troops would even consider shooting at French soldiers.

But France's defense ministry said today it would contribute up to 2,000 French troops to the U.N. operation.

A 37-member U.S. military team from Italy arrived in Uganda today to take part in an international effort to assist the refugees in eastern Zaire, said Maj. Bryan Holt, a spokesman for the U.S. European Command in Germany.

Holt said the team consists of ``medical, engineering, civil affairs'' personnel as well as ``security assistance'' people whose job is to assess what kind of security would be needed for U.S. forces in case they deploy.

When fighting first flared in the area around Uvira on Lake Tanganyika early last month, 1.1 million Rwandan Hutu refugees living in about 40 camps along Zaire's eastern border began to flee.

As many as half of the 700,000 refugees registered in the five Goma-area camps in September may now be at a new camp west of Mugunga. The others have moved into neighboring Uganda, are wandering in northeastern Zaire or have gone as far west as Kisangani, 325 miles away. Some _ maybe several thousand _ have decided to return home to Rwanda.

The Rwandan Hutus fled to eastern Zaire in mid-1994 after the Hutu government orchestrated the slaughter of at least 500,000 people, most of them Tutsis. They have refused to return home because they fear retaliation.

Rwanda wanted to drive the refugees away from its western frontier to stop invasions by Hutu soldiers and militia from the camps. Zaire, which has used those soldiers and Hutu militia to its own ends, has now paid for it with war.

Rwandan presidential adviser Ephraim Kabayija blamed the international community for the war.

``If they had followed our warnings _ that these camps should be closed with urgency _ the situation would not have blown up to this extent,'' Kabayija said.

But aid agencies say they are not to blame.

``Our job is to take care of refugees,'' Lino Bordin, U.N. High Commissioner for Refugees chief in Goma, said before leading an evacuation of aid workers out of Zaire into Rwanda on Nov. 2. ``We are not politicians.''

Instead of throwing millions of dollars at the problem, donors should stabilize the region by improving economic and political cooperation and rebuilding Rwanda, said Randolph Kent, former U.N. humanitarian coordinator in Kigali.