U.S. Trade Representative Clayton K. Yeutter said yesterday that the United States won major "deal-breaker" agreements that will open Canadian markets to sales of U.S. wine and make it easier for American companies to sell sophisticated telecommunications services in Canada.

Listing other U.S. gains in the free trade pact with Canada agreed to over the weekend, Yeutter said American manufacturers of furniture and paper products will benefit from the elimination by 1994 of all tariffs on their shipments to Canada. Canadian tariffs on those products now stand three to four times higher than the U.S. duties.

Looking ahead to the congressional review of the pact, Yeutter said, "Members of Congress ought to embrace and support this product because it has so much economic potential over the next 20 years. This agreement will be a major winner for the United States and Canada."

Congressional reaction has been muted so far, with lawmakers waiting for more details before making comments. A 38-page text containing the "essential elements" of the agreement, signed by negotiators from both countries, was made available yesterday and Yeutter and Treasury Secretary James A. Baker III will brief members of the Senate Finance Committee today.

Prime Minister Brian Mulroney told the House of Commons in his first assessment of the agreement that the pact will produce lower consumer prices, higher wages and greater national prosperity for Canada, Reuter reported from Ottawa. "We have set a course for a stronger, more united and a more prosperous Canada," he said.

But opposition leaders accused him of putting Canada up for sale because the agreement eases restrictions on foreign investment and ends limits on U.S. purchases of energy. "This country will become a satellite of the United States," said Liberal Party leader John Turner. Ed Broadbent, head of the New Democratic Party, demanded an immediate election and accused Mulroney's Conservative government of seeing Canada as "one huge cash register" for the United States.

Yeutter acknowledged that the deal almost fell apart for the third time just five hours before the midnight Saturday deadline when Canada insisted that the pact prevent Congress from passing future trade laws that could hurt Canada.

"It brought a total impasse. There was a decision on the part of Canada to go home," said Yeutter, who added that the U.S. negotiators were "perplexed" that Canada should raise that issue when "we essentially had a deal."

After explaining that no agreement can stop either the U.S. Congress or the Canadian Parliament from passing legislation, Yeutter and Baker turned to lawyers led by Yeutter's general counsel, Alan Holmer, "and told them to be creative," sources said.

They came up with a new wrinkle that allows either government to challenge a trade law before an impartial panel that would decide if the law violates the agreement. If it does, the executive branch would try to get the law changed, but there is no obligation on the part of legislators to follow through. If the law stands, however, the country that is hurt can act, either by passing a similar law, taking comparable action or, in an extreme case, pulling out of the agreement.

Canadian Ambassador Allan E. Gotlieb called that provision "innovative and new in the world of international law," and said it requires U.S. lawmakers to specify Canada if they want trade bills to affect that country. But a U.S. trade official said that provision gives Canada no greater authority than it already has under international trade laws.

Nonetheless, that provision may be a sticking point with Congress since it appears to place limits on the authority to pass trade laws.

Congressional aides also have raised constitutional questions about the solution to Canada's major demand in the 16 months of negotiations -- a binding, binational method of settling disputes. This would substitute a special panel for each nation's judicial review of decisions in unfair trade cases. But Canada failed to win a major point -- the binational handling of all unfair trade complaints from the beginning.

Yeutter said other possible sticking points are provisions dealing with energy, especially one giving Canada access to oil from Alaska's North Slope and another removing U.S. barriers to imports of Canadian natural gas. The head of the Texas Independent Producers and Royalty Owners Association, John E. Watson, attacked that part of the agreement as a "hidden threat to the energy security of the United States."

But Yeutter said energy consumers should be pleased with the agreement.

Parts of the pact granting exemptions to each country from the other's meat import laws might also draw attacks from the U.S. beef industry, and maritime interests may object to a bar on further expansion of laws restricting shipments between U.S. ports to American-flag ships, Yeutter said. To sweeten the deal for the maritime interests, however, any North Slope oil sold to Canada must be shipped on U.S. vessels.

While most of the attention has focused on congressional reaction to the pact, Canada's constitution gives its 10 provincial premiers a critical role in putting its many provisions into effect. They have balked in the past at implementing international agreements signed by the national government.

"We need assurances the premiers will go along before Congress votes or there will be no congressional approval. How Canada does that is up to them," said a senior administration official.

Gotlieb agreed. "We have to provide assurances beforehand that the {provincial} laws {implementing the agreement} will be passed," he said.

As an example of some of the trade-offs involved in reaching an agreement, Yeutter revealed that the United States could not get beer included in a provision easing restrictions on the sale of American wine and liquor because Canada demanded in return an end to quotas on its sugar shipments. Yeutter said the Reagan administration could not do that because giving Canada larger sugar quotas would hurt key U.S. allies, especially the Philippines and nations of the Caribbean Basin that are traditional sugar suppliers to this country.

"It fell out as we put together a total agriculture-distilled beverage package," said Yeutter.

U.S. brands of beer are becoming increasingly popular in Canada, but to be sold in that country the beer is made there under license. While that produces profits for U.S. beer companies, it takes jobs away from American workers and farmers who grow the grains used to make the beer. Ending barriers to U.S.-made beer, moreover, was considered a deal breaker for Canada because of the political clout of its beer industry.

Yeutter, though, said getting rid of barriers to sales of American wines and liquor was critical to the U.S. stand. He said the agreement ends Canada's "discriminatory pricing" that raises the cost of American wines "substantially higher" than the cost of the Canadian-made competition.

Chrysler and Ford, two of the Big Three U.S. automakers, praised the pact for limits it imposed on Canada's program to get Korean and Japanese companies to assemble cars in that country, using some Canadian parts, for duty-free shipment to the United States.