The Salvadoran defense minister declared today that his country has a right to high levels of U.S. economic aid because it is shedding blood for the defense of western democracy in the 5-year-old war against leftist insurgents.

"We now have the right to receive the aid that the historic moment determines," Gen. Carlos Eugenio Vides Casanova said in a Soldier's Day speech. "For this reason, with all respect, I tell friendly nations to regard these next three years as the critical term to support our people with all required economic aid, because only this way would we be strategically and permanently eradicating the causes of violence."

U.S. economic and military aid to El Salvador have risen from a total of $166.9 million in 1981 to $446.8 million this year, comprising $320.8 million in economic aid and $126 million in military aid.

The general emphasized economic rather than military aid in his speech and declared that the armed forces "have the equipment necessary to meet our tactical and strategic needs, human as well as material." But El Salvador's economic needs also must be met as part of the war against the leftist rebels.

"Friendly countries must understand that, having achieved another step in the democratization of the nation, and having created the present military circumstances, sufficient economic support is required to carry out, in the strategic part of this struggle, the task of guaranteeing our productivity . . . .

"If at this point we are denied the right we have to receive this aid, because we have sacrificed our lives and spilled our blood for western democracy, the five years of war would be useless before the world."

Vides Casanova also went out of his way to emphasize what he said was the military's determination to support the transition to democracy under President Jose Napoleon Duarte after years of direct and indirect military rule marked by jockeying among rival officers with competing political backers.

"With pride I declare that the armed forces are now a monolithic entity where internal antagonisms have disappeared and where a unifying spirit of discipline and single purpose has been achieved that guarantees an irreversible victory in the military struggle," he said.

Against that background, Vides Casanova reminded political leaders of what he called the Army's function as "neutral and independent guide" in national life. This appeared to be an allusion to his rejection last month of a demand by rightist parties that March 31 legislative elections be nullified after Duarte's Christian Democratic Party won an unexpected majority in the National Assembly.

Duarte has said the Army also has rejected a number of suggestions from rightist figures for a military coup since the U.S.-backed president was installed last June after defeating the right-wing candidate, Roberto D'Aubuisson. Without referring to this directly, Vides Casanova called on Salvadorans to set aside political differences and work for economic revitalization.

The political content of his comments underlined the decisive role still played by the armed forces in Salvadoran political life. For this reason, observers noted that he gave a qualified blessing for Duarte's dialogue with the insurgent leaders.

"With respect to peace, we wish to say to the president that he has all constitutional right to seek it within the framework of the fundamental laws of the republic," Vides said, with Duarte seated nearby.