Nearly six months after the Brandt Commission made its urgent plea for a new economic relationship between the rich and poor countries of the world, negotiations between the industrialized countries of the North and the developing countries of the South remain deadlocked.

A special session of the United Nations scheduled next month to launch global North-South negotiations on trade, energy, food, financial aid and the international monetary system is expected to end again in disagreement on the format and content of the negotiations. Diplomats have been unable to agree even on the agenda for the U.N. session.

A North-South summit meeting of the leaders from 20 to 25 industrialized and developing countries has still not been arranged, even though it was recommended by the international and business leaders who made up the Brandt Commission. When the idea was brought up at last month's Venice summit of the seven major industrialized countries, President Carter's reaction was lukewarm and British Prime Minister Margaret Thatcher was outspokenly hostile.

The problem is that none of the nations in the North or South have accepted the Brandt Commission's conclusion that it is in their mutual interest to establish closer economic cooperation.

The blue-ribbon commission headed by former West German chancellor Willy Brandt recommended that the richer nations of the North provide more financial aid and food to poor countries of the South. It also suggested a reform of international financial institutions such as the World Bank and the International Monetary Fund to make more loan money available to developing countries on easier terms to expand their economies and make it easier for developing countries to sell their exports to the North instead of trying to block them as unwanted cheap competition.

In return, Brandt argued, the industrialized countries could bargain for a better deal on oil and other raw materials imported from the South and would eventually create in healthier developing countries a bigger market for exports from the North.

But this logic, arrived at by the Brandt Commission to appeal to the richer industrialized countries, has instead met determination to help themselves first in the current climate of recession, inflation and high oil prices. The industrialized nations are tightening their belts rather than spending more freely and considering new barriers against cheap imports rather than welcoming them.

The developing countries remain equally determined to negotiate only for the full loaf they believe is owed them after centuries of colonial exploitation and they want to keep the talks inside the United Nations. They still see themselves as victims of discrimination by institutions such as the World Bank and IMF, which are intended to help poorer nations. They believe the industrialized nations have decided to stall indefinitely on North-South negotiations.

"The chances of a favorable reception of the Brandt report are much worse today than they were 12 months ago," said John Lewis, a development assistance official for the industrialized countries' Organization for Economic Cooperation and Development, at a recent North-South roundtable discussion of the impact of the Brandt report. The roundtable, sponsored by the Washington-based Society for International Development, brought together 40 politicians, diplomats and officials from nations of the North and South for three days at the University of Sussex in Brighton.

"The Brandt report is four years too late," claimed Ismali-Sabri Abdalla, chairman of the Third World Forum. "It's come at a time of skepticism and disillusionment in the South and inflation and recession in the North."

He and others representing the South also suggested that Brandt's recommendations really were aimed at propping up the industrialized countries by convincing them to give the South just enough aid to "reinforce the present economic exploitation" of the cheaper labor and natural resources of countries in the South.

Questions were raised about whether even countries within the North or South could agree among themselves on priorities. The United States and Europe are at odds with Japan on trade, for example. The poorest countries of Africa have little in common with rapidly developing countries of the South, such as Nigeria, Malaysia, South Korea and Singapore.

At a time when Brandt urged much greater international cooperation, nationalism seems to be increasing in which is being called the "me decade for nations." African development officials Samir Amin and Adebayo Adedeji argued, for example, that African countries need to "delink" their economies from their former colonial masters before they can join the new North-South linkages as truly independent nations.

Andrew Young, former U.S. ambassador to the United Nations, warned that leadership on North-South issues is not going to come from the United States.

"It is important to face the fact that the U.s. is incapable of making a decision at this point," he said. "U.S. officials won't even face these questions. Their first reaction is, "What will we lose?'"

One of those officials, Douglas Bennet, administrator of the U.S. Agency for International Development, insisted that the United States was "not paralyzed" but "preoccupied with trying to find the solutions to its own problems."

Bennet said the United States faced the challenge of having "for the first time to adjust to scarcity. You've got a democracy waiting for a new consensus. It's not true to say we know the answers and refuse to act. We just don't know what the answers are."

Officials from other parts of the world noted that the Brandt report received little public attention in the United States, selling 15,000 copies in paperback there, compared to 40,000 copies sold and several parliamentary debates on the subject in Britain. Yet British Prime Minister Thatcher has been one of the most reluctant leaders to agree to North-South negotiations, calling the concept "jargon" and explaining that Britain was not financially ready to take on new obligations to poorer countries.

In its first official response to the Brandt report, Thatcher's Foreign Office this week told Parliament that "the same economic conditions creating the current plight of many developing countries also make it more difficult for us to respond to calls for increased aid."

It poured cold water on Brandt's recommendations for major changes in the world's financial structure, saying the British government "believes strongly in the merits of the present world economic system, with its wide reliance on open markets for trade and financial flows." It was up to the developing countries of the South to provide "a climate of confidence for extermal investors and stable conditions in which they can operate.