OTTAWA, JUNE 4 -- Canada's federal and provincial leaders, still at odds less than three weeks before a constitutional deadline that could preserve or doom the 123-year-old Canadian confederation met for the second straight day today in a desperate attempt to resolve the crisis.

Weary after marathon talks Sunday, Prime Minister Brian Mulroney and the nation's 10 provincial premiers pressed ahead in their bid to save the Meech Lake accord, whose collapse threatens to alienate French-speaking Quebec, nullify terms of the existing confederation and drive at least some provinces to seek union with the United States.

The accord, signed by provincial leaders three years ago last Sunday, consists of a series of proposed consitutional amendments designed to induce Quebec to endorse the country's 1982 charter, which it alone among Canada's provinces has not done. Since the accord, however, three of Canada's English-speaking provinces have objected strongly to the amendments, arguing that in defining Quebec as a "distinct society" they empower it with special rights, privileges and powers not granted the English-speaking provinces.

Various proposals designed to modify the accord have been put forth by a parliamentary panel and by the signatories themselves, but so far a settlement has proved elusive. Terms of the agreement specified that it would become void if all 10 provinces did not ratify it by June 23, a deadline that many officials now say seems impossible to meet.

Recent polls suggest that residents of Quebec, who rejected secession in a 1980 referendum, are more inclined than ever to separate from the rest of Canada because of what they see as a refusal by English-speaking Canadians to recognize their French heritage and language. Quebec leaders, believing the "distinct society" amendments essential to protect the province's uniqueness in North America, have suggested they may seek a separate nation if their demands are rejected.

Entering the meeting in Ottawa today, Quebec Premier Robert Bourassa told reporters: "If there is no political will to find a solution, it's impossible to reach an agreement."

Ontario Premier David Peterson, however, said he had some fresh ideas aimed at breaking the deadlock and that he anticipated at least one or two more days of talks. "It depends on the goodwill of everyone," he said.