President Jose Napoleon Duarte is being treated in the United States for cancer of the stomach and liver and is "on the verge of death," the acting chief exective said.

The 62-year-old Duarte, one of the hemisphere's staunchest U.S. allies, was at Walter Reed Army Medical Center in Washington, D.C.With prospects for Duarte's return to the presidency dimming by the hour, Salvadorans face additional uncertainty heaped upon an already confusing national panorama of war and economic stagnation.

Vice President Rodolfo Castillo Claramount, the acting chief executive, told journalists on Wednesday "it has been confirmed that President Duarte has a cancerous bleeding ulcer in the stomach. Today's (ednesday's) examination . . . showed that the liver is also affected by cancer."

Castillo Claramount said an official prognosis would be issued Thursday by doctors at Walter Reed, where Duarte has been hospitalized since Tuesday night.

The vice president read part of the 41st Psalm, which talks of people hoping for their enemy's death, then added: "Unfortunately in the past days, this kind of situation has come up in the country."

"I ask for a minimal expression of humanity, of charity. A fellow man's pain cannot be toyed with. No one can doubt the word of a man on the verge of death, who has had the courage to say it," he said.

Duarte is in the final year of his five-year term, and his image and influence have been so eroded that his absence is expected to have little impact on El Salvador's already staggering problems.

When he assumed the presidency in 1984, a popular and dynamic Duarte was hailed as a figure of historic proportions who would lead the country out of decades of conflict and widespread misery. But very little of what he promised has been wrought.

An 8-year-old civil war between U.S.-backed government forces and leftist guerrillas continues unabated.

The economy is in a shambles. The average Salvadoran's real income is almost 40 percent below what it was at the start of the war. About 500,000 people _ 10 percent of the population _ have been displaced to squalid shantytowns and refugee camps.

Because of the lack of security, investment is virtually nil.

Duarte's absence "could even make things easier. In himself, because of the way he is, he is an obstacle," businessman Tomas Pineda commented Wednesday before word came of the gravity of Duarte's illness.