The chairman of 10-nation creditor group considering ways to rescue Zaire from economic collapse said yesterday that the results of a two-day meeting here were "satisfactory to us all and the outcome was a happy one, thank God."

The chairman, Belgium is U.N. ambassador, Andre Ernemann, said it was "a certainty" that the immediate humanitarian needs - food, medical help, fuel and spare parts - for the war-torn, debt-ridden country would be met over the next three months as part of an emergency effort.

Zaire's representative, Bokana W'Ondangela, said he shared the chairman's positive assessment of the meeting.

It was also clear, however, that several countries - including the United States, France, Italy and Britan - wanted more precise information from Zaire before offering additional aid. One country, Iran, said it would not participate in the rescue operation.

It was also apparent that anything more ambitious than the initial emergency aid program, in terms of assuring Zaire's long-term financial survival, would take many months to develop and would be heavily dependent on how well a virtual takeover of the country's key financial institutions by international experts works out.

The Western creditor nations have insisted that a precondition for any major new investment, Zaire. Must discipline its central bank and reduce the inefficiency and corruption that have plagued the government of President Mobutu Sese Seko for 12-years.

Zaire has agreed to accept an official of the International Monetary Fund as the most powerful authority in the central bank and another international specialist as chief comptroller in the Finance Ministry, to guide public spending.

Ernemann said the group would meet again in the fall, to assess the terms of "painful" new credit agreement that Zaire is trying to arrange with the IMF, and then again at the end of the year on results of the changes demanded by the creditors.

The IMF loan is seen by Western representatives here as the key to any long-term program. While Zaire has estimated it needs at least $1 billion in new investment, delegates said it was clear that nobody would be stepping forward with that kind of money until the IMF moves.Creditors also will want to see whether the country's military security can be assured. Last month, for the second year in a row, Zaire was invaded by Katagan rebels.

Although the meeting here was meant to discuss the so-called Mobutu plan, which includes long-range investments, the dire immediate needs shifted the focus to a three-month emergency program that Zaire estimates will cost about $116 million.

Ernemann acknowledged that beyond those initial needs, things "become more complicated," largely because of what another official calls the "nightmare" of Zaire's chaotic economic statistics. The lack of reliable data produces skepticism among donors about how much is needed and how much Zaire can help itself.

Ernemann referred to the pressing for restrictions on imports to help the need for better currency management, huge balance of payments deficit, and for the return to European owners of firms that had been taken over by Mobutu. He also called for improvements in aid programs to eliminate corruption.

Security is a key element. In addition to the sharp drop in copper prices over the past two years, Zaire's sharply curtailed copper and cobalt exports have been the invasion of mineral-rich Shaba Province, bringing the economy to the brink of collapse. There is no Western agreement on how to defend against future attacks or how to shape up Mobutu's largely undisciplined and unpaid 40,000-man army.

Host Belgium, with some $6 billion invested in its former colony, is by far the most concerned of the creditor nation.

Some $70 million in immediate aid was pledged, although it must be approved by governments back home. Virtually all of this was aid already earmarked for Zaire that is now to be speeded up.

West Germany pledged about $40 million, with smaller preliminary pledges from the World Bank, the European Common Market emergency fund, Canada, the Netherlands and Belgium.France said it would act but was not yet sure how.

The most puzzling response came from Iran, which said it had its own money problems and would not contribute. Another major oil producer, Saudi Arabia, was scheduled to take part in this meeting but cancelled at the last minute. This raises the question of whether the Persian Gulf states have decided to turn their back on Mobutu.