Argentina's new Army government will continue to insist that Britain agree to negotiate over the Falkland Islands before accepting a permanent cessation of hostilities in the South Atlantic, Foreign Ministry officials said today.

The diplomatic stance was indicated this afternoon by newly inaugurated Foreign Minister Juan Aguirre Lanari, who said "a de facto" cessation "of hostilities exists for Argentina in the South Atlantic" but that Argentina would continue seeking to resolve the conflict on the basis of United Nations resolutions that call for talks on Argentina's claim to the Falklands.

Government sources later confirmed that Lanari had not altered the position adopted by former foreign minister Nicanor Costa Mendez that Argentina could not agree to a final end to the hostilities with Britain--thus losing its last measure of diplomatic leverage--without receiving a promise of negotiations in return.

Lanari's statement in a press conference echoed a note delivered by Argentina to the United Nations more than two weeks ago, before the installation of the new Army government of Reynaldo Bignone. That statement said a de facto cessation of hostilities existed in the South Atlantic but it would be "precarious" until British troops were withdrawn and negotiations begun.

Britain has not accepted formal talks with Argentina on the Falklands and has refused to withdraw the forces that recaptured the islands June 14. Instead, Britain has called on Argentina to indicate it will not continue military action and has said several hundred Argentine soldiers still being held by British forces will not be released until the cessation of hostilities is agreed.

Lanari said this afternoon that Argentina was making efforts through the United Nations for the return of the prisoners, but he refused to specify what was being done.

Other government officials said that Argentina was privately seeking to arrange a settlement with Britain but that the Foreign Ministry did not expect a quick conclusion to the issue. "What's the hurry?" one ranking official said. "We're not the ones holding the hostages."

Government officials also indicated that the Bignone government was hoping the United States would help arrange a solution of the conflict acceptable to Argentina and that the future of U.S.-Argentine relations could depend on the U.S. stance.

Lanari said U.S.-Argentine relations had "deteriorated" and future ties between the two governments would depend "on concrete acts."

"The time for words has passed," he said.

The new foreign minister held the press conference after an address to diplomatic officials here in which he said his "first priority" would be "to continue defending the sovereign rights" of Argentina over the disputed territory, which Argentina invaded April 2.

The government stance on the end of hostilities with Britain does not mean that the military leadership is actually planning new attacks on British forces, government sources said.

The top rank of Army division generals, now the most important source of power in the country, decided shortly after Argentina's surrender not to continue fighting, and it imposed this decision on former president and Army commander in chief Leopoldo Galtieri. Galtieri was subsequently forced to resign.

Since then, debate within the government has focused on how Argentina should continue its campaign for the Falklands. While some military leaders have been reported to believe that Argentina should privately indicate its agreement to a halt to hostilities, Navy leaders and other top commanders have argued that Argentina should adopt a policy of "harassment" against Britain, leaving open a permanent threat to renew military operations.

This policy, now adopted at least in part by the Bignone government, would force Britain to divert substantial resources toward the defense of the islands for the indefinite future unless it accepted some of Argentina's demands.

"Really, the responsibility for the future development of events falls on Britain," Lanari said.

Lanari, who served as Argentina's ambassador to Venezuela before becoming foreign minister and was previously a conservative politician, reiterated that Argentina intended to strengthen its relations with other Latin American countries and be "independent" diplomatically following the Falklands conflict.

However, echoing the words of a recent speech by the new Army commander in chief, Gen. Cristino Nicolaides, he said that "by tradition and culture, Argentina is and will be a Western country."

The statement strengthened previous indications by the Bignone government that it would not redirect Argentina's foreign alliances toward the nonaligned nations or the Soviet Bloc as a result of the conflict with Britain, as Galtieri and a number of political leaders had recommended.

Instead, Lanari indicated, Argentina would return to its traditional foreign policy of pragmatically pursuing its own special interests--such as the Falklands claim--above any particular alliance while loosely identifying itself with the interests of the United States and Western Europe.

Argentina followed this type of narrow and often contradictory policy off and on for generations before the inauguration last year of Galtieri, who originally sought to establish closer ties between Argentina and the United States while distancing his government from the nonaligned nations group and such countries as Cuba and Nicaragua.