The Ethiopian government is setting the stage for "an impending new disaster" at the Ibnet famine-relief camp by removing U.S.-supplied tents intended to shelter 20,000 residents and by failing to transport supplies needed by another 40,000 refugees leaving the camp, the United States charged last night.

M. Peter McPherson, administrator of the Agency for International Development, told The Washington Post that the actions by the government of Lt. Col. Mengistu Haile Mariam "threaten a major outbreak of cholera and other disease" at the camp and will leave many refugees streaming out of Ibnet without food or equipment to sustain themselves. He said the situation marks the second time in two months that the camp in the Gondar region of the famine-stricken country has been involved in a power play that could bring death or disease to thousands.

At the end of April, the government expelled tens of thousands of famine victims amid treacherous rains and with little or no food, seed or tools. At the time, American and other relief officials predicted that if the expulsions continued, a large percentage of the ousted refugees would die. After widespread protests, the government said Ibnet would be reopened to those wanting to return.

Since then, an army of destitute peasants has converged on the camp, and McPherson said the population, about 60,000 in April, is now estimated to be 60,000 to 80,000. Recent reports from Ethiopia said a large, apparently voluntary new exodus from Ibnet has started with the help of Ethiopian and western aid organizations. But McPherson said AID received information yesterday about actions by the Ethiopian government that threaten to prevent U.S. assistance from reaching the refugees.

According to U.S. estimates, he said, about 40,000 camp residents are willing and able to return home and attempt a new start at subsistence farming. He said about 20,000 others must remain at the camp indefinitely. To help those wanting to leave, McPherson said, the United States is trying to get sufficient supplies to Ibnet so each exiting family has seed, hoes, blankets and enough food to sustain it for several weeks.

He said the United States also contracted with the American-Jewish Joint Distribution Committee for delivery to Ibnet of 1,000 large tents to shelter the 20,000 persons remaining in the camp and of equipment to dig new wells that can provide unpolluted water. However, McPherson added, AID representatives said yesterday that the Ethiopian army abruptly loaded the tents onto 25 trucks and removed them to Addis Ababa.

Because the forced evacuation in April was accomplished by burning the refugees' grass huts, McPherson said without tents, those remaining in the camp face danger from exposure and disease. He also said food, seed and other supplies intended for those leaving is not reaching the camp because the Ethiopian government has refused to provide enough trucks to transport it there quickly enough.

"The situation is especially acute because there are only a couple of weeks left in the planting season," he said. "Time is running out in a way that confronts those who want to leave with a bleak choice: They can wait for the supplies and miss the chance to plant, or they can try to leave now without the food and equipment they need to sustain themselves . . . ."

McPherson said enough food remains in Ibnet to feed those there for about two weeks.