ABIDJAN, Ivory Coast (AP) _ The United Nations is moving too slowly to put in place the Liberian peace plan it brokered a month ago, causing the deaths of hundreds of children from starvation and disease, relief agencies say.

Right after the peace agreement was signed July 25, the United Nations ordered the Ivory Coast to close its border with Liberia. That blocked a route private aid agencies had been using to get food and medicine to an estimated 250,000 refugees pinned down in rebel territory.

With no more aid, nearly 100 children are dying daily of starvation and disease, said Monique Nagelkerke, an aid worker for the Dutch branch of Doctors Without Borders.

U.N. special envoy Trevor Gordon-Somers promised to quickly arrange for U.N. observers to be posted at the border to check shipments for arms and re- open the frontier to aid workers. So far, only an advance team of 29 has arrived.

U.N. officials claimed chief rebel leader Charles Taylor was using the convoys to transport weapons, which the agencies denied.

Aid groups say the special U.N. envoy to Liberia, Trevor Gordon-Somers, is hampering humanitarian aid to avoid upsetting the factions.

The Nigerian-led West African army, sent into Liberia to crush Taylor's rebellion in 1990, has long lobbied for the Ivorian border to be closed to keep aid from reaching enemy territory.

''I would love to invite Trevor Gordon-Somers to come and look at the children dying. He's into politics and just doesn't care about the kids,'' Nagelkerke said.

Other aid agencies, including the U.S. Catholic Relief Services and the French Action International Against Hunger, have made similar allegations about the U.N. role.

Liberia's interim President Amos Sawyer warned last week that the peace accord could collapse unless U.N. officials speed disarmament plans. At least 150,000 people died in the three-year war, which displaced more than half this nation of 2.6 million.

The head of the U.N. observer mission, Col. Laszlo Forgacs of Hungary, has blamed bureaucratic bottlenecks at U.N. headquarters in New York.

Gordon-Somers was in Monrovia on Tuesday, but was unavailable to the media. Other U.N. agency chiefs said only Gordon-Somers could comment.

Aid officials reached in Monrovia said Gordon-Somers met with them Monday night and promised to send two U.N. workers to the Ivory Coast to inspect an aid convoy blocked at the Liberian border.

He also promised that another 40 monitors would arrive in the next two weeks, but did not know when the full team of 300 would be in place, said the relief officials, who spoke on condition of anonymity.

''If children are dying, that's not the Ivory Coast's fault. Talk to the United Nations,'' said Ambassador A. Traore of the Ivory Coast Foreign Ministry on Tuesday. In the view of U.N. officials in New York, Ivory Coast convoys are now less important than they were before the truce because other routes within Liberia have opened.

But relief agencies said those routes are not secure.

''What little is getting through is not enough to keep people alive,'' said Nagelkerke. ''The only answer is to open the border, or the children are just going to continue dying.''

The war began when Taylor invaded in 1990 to topple the government of then- President Samuel Doe. The fighting turned into factional bloodshed.

The peace accord calls for creation of an interim government to rule Liberia until new elections are held next year, but the government has not taken power because the disarmament process has not begun.