The International Court of Justice rejected today the United States' claim to all of the valuable natural resources of Georges Bank off Nova Scotia and Massachusetts, giving Canada rights to a portion of the waters and sea bed.

In a 4-1 decision, a special panel named to consider the dispute over the bank area created a boundary starting at the northern end of the Gulf of Maine that gives Canada about one-sixth of the bank, along with adjacent waters to the east.

The bank is rich in scallops, cod, halibut, haddock and other catches, and is believed to have significant deposits of oil and natural gas.

The ruling, aimed at ending a 20-year dispute over the area, was termed a "compromise" by a senior U.S. official who participated in the case. About one-half of the disputed section of the bank was given to each country.

"Neither side got what it was after," the U.S. official said, adding that the court rejected most of the arguments put forward by both nations in support of their claims. The United States asked for control of the entire bank and adjacent waters, while Canada wanted control of about 35 percent of the bank.

Both countries have said they will accept the ruling, unlike another case currently before the court that concerns the U.S. role in the mining of Nicaraguan harbors. The United States has said it will not accept the court's jurisdiction in that case and is currently arguing the issue before the court.

A top Canadian official who also was involved in the case said the northern and northeast waters given his country by the ruling are "among the more productive areas of the bank." If the court had granted the entire U.S. claim to the disputed area, now fished by both sides, the Canadian economy would stand to lose about $80 million a year, he said.

The Canadian also said the portion of the bank given his country was regarded as a "promising" area for oil and gas exploitation.

Estimates of the size of the energy resources on the entire bank differ, but one U.S. Geological Survey expert has said it could contain 1.5 billion barrels of oil and 12.2 trillion cubic feet of natural gas.

It was not clear how the decision would affect the catches of U.S. fishermen. U.S. officials declined to say if the new boundary line would reduce the size of the catch.

The five jurists were from Canada, the United States, France, Italy and West Germany. Both Canadian Judge Maxwell Cohen and American Judge Stephen M. Schwebel voted for the decision. Judge Andre Gros of France cast the sole dissenting vote.

U.S. officials said the decision was significant in terms of international law because it was the first time the court had ruled on both water and sea bed rights together.

There are about 300 maritime boundaries in dispute around the world, one U.S. official said, and the subject has become increasingly contentious in recent years as many countries have extended their claims to adjacent waters to the 200-mile limit and, in many cases, claimed exclusive economic rights.

Asked if the decision would help other countries resolve their maritime boundary disputes, the senior U.S. official said, "Both the United States and Canada are indeed hopeful that we have struck a positive blow for the resolution of disputes through adjudication."

But the effect is "really going to depend" on how other countries receive the panel's decision, he said.

Because the court laid out a compromise in the U.S.-Canada case, he said, some nations might seek political rather than judicial solutions to their boundary disputes.

The senior American official said his team had not had the time yet to consider the implications of the decision for three other maritime boundary disputes between the United States and Canada. The three concern the Dixon Entrance between ld chills." State and Vancouver Island, and the Beaufort Sea between the Yukon and Alaska.

The dispute over the waters began in 1964 over issuance of Canadian gas and oil exploration permits. It led to both countries rejecting each other's rights in the area.