The United States and Canada, embroiled in a seven-month-old fish war, have reached a tentative 10-year accord on fishing rights off the northeast coast.

U.S. negotiating team officials said an agreement has been drafted spelling out quotas and percentages of fish each nation can catch.

"After two and a half years of negotiating, the two countries are pretty close to agreement; all that's left is some fine tuning," said David Preston, a special staff assistant on international affairs for the National Marine Fisheries Service here.

Douglas Marshall, a State Department official, was also quoted as saying, "We've almost agreed on an overall fisheries package for the East Coast." Ambassadors for both nations will meet in Washington next week.

The agreement carves out catch limits in a disputed fishing area on the Georges Bank -- one of the most prolific in northeast waters, with an annual haul of over $60 million.

A Georges Bank boundary dispute, which arose when both nations imposed a 200-mile limit in 1977, will be decided by the World Court in the Netherlands.

The agreement would also ostensibly end an increasingly bitter dispute over Canada's ban last year on American fishermen in its waters. The United States followed with a similar decision to expel Canadian fishermen from American waters.

The "fish war" escalated this week when fishermen from Maine set up a blockade preventing a Canadian ferry laden with 10 trailer-truck loads of cod and haddock from docking in Portland en route to Boston.

Meanwhile, fishermen from both sides have been fishing on Georges Bank. Canada claims that the area is within its boundaries, which overlap the U.S. territorial line at that point. The United States has proposed a natural boundary -- the Fundian Channel, which runs between Georges Bank and Brown's Bank, splitting from the Gulf of Maine between Nova Scotia and Maine.

Rep. David R. Emery (R-Maine), a member of the House Merchant Marine and Fisheries Committee, called the tentative agreement "a major breakthrough that will hopefully lead to a fair agreement."

No details have been released on the pact.However, sources said U.S. negotiators have given Canada the right to fish for squid in U.S. waters in return for the right to catch ocean perch in Canadian waters. The accord sets quotas on the harvesting of cod, haddock, mackerel, pollock, herring, scallops, silver hake and, for the first time, lobster, as well as other species of fish.