The president of Brazil and the foreign ministers of Canada, Norway and Venezuela called today for strengthening the U.N. role in resolving global crises, thus setting an introspective theme on the opening day of the General Assembly's month-long foreign policy debate.

Brazilian President Joao Baptista de Oliveira Figueiredo launched the annual parade of heads of state and foreign ministers by warning that the United Nations has been "transformed into a forum for sterile confrontation" at a time when threats to the peace of nations are at their height.

Other speakers, in tackling the crisis of confidence in the United Nations, praised the first annual report of its secretary general, Javier Perez de Cuellar, which admitted the U.N.'s failings and warned of "international anarchy" unless the institution is used more effectively for negotiating differences before disputes reach the crisis stage.

Venezuelan Foreign Minister Jose Alberto Zambrano Velasco charged that the U.N.'s reputation had been "shattered" by its inability to act in Lebanon and elsewhere. He praised the "courageous ideas" for reform in the secretary general's report, and said that Venezuela would submit proposals to Perez de Cuellar to resolve its long-standing territorial dispute with Guyana.

Canadian Secretary of State for External Affairs Allan J. MacEachen said that the U.N.'s ability to manage crises had been called into question by divisions within the Security Council, a cycle of ineffectual resolutions, and a tendency toward polemics. He welcomed the secretary general's proposal to "play a more direct role in bringing urgent matters before the council."

Norway's foreign minister, Svenn Stray, was even more specific in his endorsement of Perez de Cuellar's suggestion that the council monitor disputes and initiate negotiations before the crisis stage is reached. He suggested that the secretary general take the lead by bringing danger signals to the council's attention and by engaging in "fact-finding" on an organized basis.

Stray also praised the Perez de Cuellar proposal that the authority of U.N. peace forces be enhanced by superpower guarantees.

Although the speakers were supportive of Perez de Cuellar's ideas, none thus far has responded to his appeal for new ideas of their own.

Brazil has traditionally opened the assembly's general debate on foreign policy, but this was the first time its president did so. The bulk of his address dealt with the need to liberalize international trade and monetary policies.

The United States is generally the second speaker, but American officials said that because of today's Jewish and Islamic holidays, Secretary of State George Shultz had postponed his address until Thursday.