Argentina's military government remained divided and apparently paralyzed here today, unable to agree on its future course and facing increasing public demand for official explanation of the defeat in the Falkland Islands.

The ruling military junta, besieged by opponents from both within and without the armed forces, met for more than three hours this morning but made almost no move to control what appeared to be widespread unrest and uncertainty following the surrender of Argentina's garrison in the Falkland Islands and violent battles between police and demonstrators in the capital last night.

President Leopoldo Galtieri's closest supporters in the government, Foreign Minister Nicanor Costa Mendez and Interior Minister Alfredo Saint Jean, did move to salvage Galtieri's faltering political position. Costa Mendez submitted his resignation as part of a proposal that all Cabinet ministers resign--giving Galtieri a chance to deflect the pressure against him by reorganizing his government.

Saint Jean tonight called in leaders of a number of political parties to brief them on the Falklands conflict and to seek their support for the government's position. But in a strong indication of the government's weakening position, the leaders of the five largest political parties, who form a group called the Multi-Party Front, stayed away from tonight's meeting.

Political sources said the party leaders, by refusing to lend support to Galtieri's administration, hoped to encourage its fall and replacement by a transitional government that would arrange democratic elections.

Government officials also offered no indication tonight that other Cabinet ministers were following Costa Mendez' lead in resigning--or whether that of Costa Mendez would be accepted. One government source said that several leading Cabinet ministers, fearful of their positions, were resisting the move. He added: "The main question now is not whether the Cabinet goes but whether Galtieri goes."

Government sources said the junta had been unable to decide how to respond to Britain's call for a formal declaration ending all hostilities in the South Atlantic. Gen. Galtieri and Costa Mendez were reported by sources to have proposed that Argentina hold out on agreeing to this condition--considered Argentina's last leverage against Britain--until Britain agreed to accept United Nations Security Council resolutions calling for negotiations.

Argentina made no formal response to the diplomatic note delivered by Britain through the Swiss Embassy here Tuesday, however, and government sources said diplomatic activity was at a virtual standstill. These sources said powerful military leaders were arguing that Argentina should announce quickly that it accepted an end to the military conflict.

Spokesmen ranging from political party leaders to local radio commentators demanded an official account of the terms of Argentina's military surrender to Britain in Stanley Monday and the status of Argentina's troops on the island. Government sources said the presidential palace and the Foreign Ministry were flooded with calls from angry citizens asking for information.

The only answer from the leadership, however, was a lengthy communique which attributed Argentina's defeat to the "superior technology" of British weapons. The communique, describing the end of the fighting as a "cease-fire" and a "partial triumph" for Britain, pointedly reported that the arrangement applied only to Argentine forces that were on the islands Monday.

Echoing reports by Argentine newspapers this week and Galtieri's national television speech last night, the communique mentioned such British weapons as infrared scopes for night fighting and lasers for guiding artillery as technology that was "totally new" when introduced in the final attack and was unavailable to Argentina on the world arms market. It also stressed "logistical support" Britain received from the United States.

The official announcement, the first since early Tuesday, made no mention of the surrender of the Argentine troops in the Falklands or of their possible repatriation.

Galtieri, who last night said only that "the battle of Puerto Argentino (Stanley) is over, was strongly criticized today for failing to provide such information or news of Argentine casualties.

Rumors of an imminent government fall swept the capital in the silence, and Argentine political sources said the ruling junta's position was precarious. "There is a vacuum of power," said one source. "If the government does not say something soon, anything could happen."

Buenos Aires was cold and quiet today after pitched battles last night between police and demonstrators calling for the government's ouster. There were strong repercussions over the police action, which began after Galtieri's spokesman called on the public to join what was already an angry crowd in the Plaza de Mayo in front of the presidential palace.

Reports said high military leaders, including leaders of the Air Force, were angry with Galtieri for encouraging the crowd to gather. When hundreds of persons began shouting obscenities at a presidential palace balcony where Galtieri had been scheduled to appear, police attacked with tear gas and rubber bullets, and rioting broke out in which protesters burned buses and built barricades in downtown streets. Gunfire broke out in several places.

Officials at the U.S. Embassy confirmed they had received a telephone threat that a bomb had been placed in the building. Argentine police were called and found no bomb, however. There were no reports of demonstrations today against the United States, which Galtieri last night called "an enemy of Argentina and its people."

Informed sources said no open movement against Galtieri had yet developed within high Army commanders, and this indicated that the president's position was still reasonably strong. But they said Galtieri, who is also commander-in-chief of the Army, would have to work hard during the next week to prevent an uprising within his service.

In an apparent effort to consolidate the necessary support, Galtieri was reported by sources to have ordered the Army's 10 top generals, who carry the title of division commander, to prepare a study on whether Argentina should continue military action against Britain. Galtieri was reported to be meeting with the generals tonight to learn the result of the study, which sources said could be decisive in determining if he remains in power.

Government sources described moderate sectors in the government as proposing that Argentina announce its acceptance of an end to the fighting with Britain as part of an endorsement of a resolution passed by the U.N. Security Council the day after Argentina's April 2 invasion.

This Resolution 502 calls for a withdrawal of Argentine forces, an end to hostilities between Britain and Argentina, and negotiation between the two countries on sovereignty over the Falklands. Some government leaders are reported to believe that if Argentina accepts an end to hostilities it could bring international pressure on Britain to accept the stipulation of negotiation.

There has been little support for a continuation of the war among civilian leaders or the Argentine media. Today, many civilian leaders called on the government to establish peace while pressing Argentina's claim to the Falklands internationally.

A variety of party leaders also called on the military to outline a plan of government that included a return to democracy by a firm date.