OTTAWA, JUNE 3 -- Canadian leaders today approved constitutional amendments recognizing French-speaking Quebec Province as a "distinct society" within Canada in exchange for Quebec's formal agreement to accept the terms of the constitution.

Prime Minister Brian Mulroney and the country's 10 provincial premiers reached accord on the language of the amendments at dawn after a negotiating session lasting more than 19 hours.

"Today, we close one chapter in Canadian history, and begin another," Mulroney said later at a formal ceremony where the agreement was signed. "Today, we welcome Quebec back to the Canadian constitutional family.

"You knew the importance of ending Quebec's constitutional estrangement," he told the premiers. "Above all, you knew that it was a time for healing in this land."

Quebec's premier, Robert Bourassa, responded: "Quebec is proud today."

Although Canadian courts had ruled that Quebec was bound by the constitution, which was signed by the other nine provinces in 1982, Quebec had refused to give its formal approval without guarantees to protect the province's language and culture.

The province's position had promoted passionate objections from former prime minister Pierre Elliott Trudeau, a staunch federalist, who broke a long political silence to argue that the concessions, among others, would weaken federal power and set in motion a process that would ultimately divide Canada in two.

The accord appeared to set the stage for a full-blown national debate, with some provincial leaders predicting it could take as long as three years to conduct national and provincial hearings and win provincial legislative and parliamentary ratification.

Only a few words of the tentative accord that Mulroney and the premiers had reached April 30 were changed in the final version approved today to accommodate objections raised by Trudeau. For example, references to a "French-speaking Canada" were eliminated and replaced by language ensuring the rights of "French-speaking Canadians." But the final version formally recognized Quebec as a "distinct society" within Canada and gave it powers to "preserve and promote" that special identity.

To win the support of other premiers, the agreement also grants to all provinces much broader discretion over provincial use of federal funds earmarked for social programs, the authority to draw up lists of names from which members of the Supreme Court and federal Senate must be chosen and gives them some control over immigration policy. Canadian provinces already have more powers than American states, and regional divisions are much stronger.

In newspaper articles a week ago that had an electric effect, Trudeau emerged from seclusion to denounce the deal. He called Mulroney a "weakling" in the English version of his manifesto and a "coward" in the French version. Later he appeared on French- and English-language radio and television programs to press his objections.

Taking an almost proprietary interest in the constitution, which had been one of the major achievements of his 15 years in office, Trudeau contended that the accord would weaken Canada and fray the links of shared values and beliefs binding the country.

The three national Canadian political parties all have backed the accord in varying degrees, although there has been a bitter split over it in Trudeau's Liberal Party. English-speaking Canadians in Toronto and ethnic groups in Canada, galvanized by Trudeau's statements, are strongly objecting.

Representatives of ethnic groups are especially concerned that individual rights guaranteed in the constitution might be overriden by courts giving greater weight to new powers granted Quebec. Some in Quebec argued that the deal does not go far enough to protect the province's "cultural security" but most favored it and many were livid at Trudeau.

After the formal signing ceremony today, aides of Mulroney indicated they knew the battle was not over but, as one said, "We're ready for Trudeau."