BRUSSELS, JULY 4 -- The Group of 24 industrialized nations agreed here today to extend economic assistance to four emerging democracies in Eastern Europe, substantially enlarging a program created last year to aid the troubled economies of Poland and Hungary.

While the unanimous agreement to provide help to Czechoslovakia, Yugoslavia, Bulgaria and East Germany did not commit the donor group to a specific new aid package, Secretary of State James A. Baker III described the decision as a necessary response to those country's political reforms and their creation of fledgling market economies.

The group, which includes the 12 European Community countries, the United States, Japan, Canada and Australia, pledged to consider any requests from the East European nations for special food assistance, economic training, investment credits and improved access to Western markets.

At the same time, the group rejected any collective aid to Romania, citing that nation's failure to meet a number of U.S.-backed political criteria approved here for the first time. It also did not agree on direct economic aid to the Soviet Union, an idea that was strongly backed by West German Foreign Minister Hans-Dietrich Genscher, with support from Italian and Polish officials here.

Baker and British Foreign Secretary Douglas Hurd restated their opposition to such aid, although Baker told reporters later that Washington would not try to dissuade advocates from pursuing it on their own. U.S. and British officials have questioned the effectiveness of economic aid to the Soviet Union in the absence of major economic reforms there -- such as removal of price controls. The United States and Britain also have tight budgets at home that make additional foreign aid difficult.

The diplomatic exchange appeared to signal a likely "agreement to disagree" at a meeting of the leaders of seven industralized nations in Houston next week, where the principal issue will be direct aid to the Soviet Union.

{In Kennebunkport, Maine, President Bush said before flying to London for Thursday's NATO summit that if the Soviets begin curtailing their defense spending, as Foreign Minister Eduard Shevardnadze suggested in a Moscow speech Tuesday, "it would be much easier for the West to give them certain kinds of economic assistance," White House correspondent Ann Devroy reported.

{Of Shevardnadze's statement that the Soviets should cut up to 250 billion rubles from defense spending over the next five years, Bush said the figures did not surprise him. But he added that "the point is that the world is changing now, and I hope they'll feel they don't need defense. And that will mean they'll free up funds to do more at home, and it will free up Westerners' willingness to try to assist on the economic front."}

In Brussels, a senior U.S. official said he was unsure if Bush would promote the newly agreed upon political criteria for economic aid at the Houston meeting. Those criteria include respect for human rights and the rule of law, free and fair elections, the introduction of market economies and a multi-party political system. Senior U.S. officials characterized the criteria as virtually unprecedented for a multinational group involved in economic aid. Normally, they said, such groups apply only standard economic tests in lending decisions.

A proposal advanced by some Western officials to establish a special $12.5 billion fund for East European countries was rejected here after the United States and several allies argued that it would duplicate efforts by other organizations, such as the International Monetary Fund. The proposal was envisioned by its supporters as providing an economic "safety net" for East European countries to draw on as needed or as a potential resource in their discussions with Western bankers.

The group earlier approved a special $1.2 billion fund for Poland that was considered a model for the much larger East European account, but opponents of the plan argued that the four countries approved today do not appear to have similar problems. Czechoslavak officials presented, nonetheless, what was described as a general request for $3 billion to $3.6 billion, while Yugoslavia sought about $1 billion and Bulgaria $420 million.

The decision to include East Germany among the recipient nations was depicted as a largely symbolic move made at West Germany's request to endorse democratic reforms there. Officials said German unification will probably occur before any aid can be arranged and that West Germany will provide virtually all the assistance needed there.

West German and Norwegian officials told the group they would be willing to provide direct monetary aid to the newly approved nations if others do the same. A senior U.S. official said, however, that the administration has no plans to seek congressional approval of additional direct aid beyond the $300 million already earmarked for Eastern Europe in its budget request now pending on Capitol Hill.

Dutch EC official Frans Andriessen, a leader of the Group of 24, said he hoped Romania would soon show "convincing signs of an irreversible process" of reform that would enable it, too, to qualify for aid. Baker said the decision to exclude Romania was linked to the complicity of that nation's leadership with the recent "violent repression" of political demonstrators, an act that he said raised "serious questions about its commitment to democratic reform and basic human rights."

Baker, reiterating U.S. opposition to providing direct economic aid to the Soviet Union, cited what he called its lack of movement toward a market economy and its continued expenditure of large sums on the military and on client states long hostile to U.S. interests. He also said Washington did not favor diverting attention from the task of supporting nations that had been the victims of repression.