Former Canadian prime minister Pierre Trudeau bowed out of national politics yesterday by announcing his resignation as leader of the Liberal Party.

The surprise announcement followed muted party calls for new leadership after the defeat of Trudeau's government in general elections last May. The Liberals had held power for 16 years, 11 of them under his leadership.

Trudeau, 60, said he was stepping down as part of the Liberal's effort to redefine their policies and rejuvenate their ranks. He said he thought "a good deal about a change of leaders, with the Quebec referendum facing Canada."

He would, he said, "continue to fight for Canada" during next spring's referendum in Quebec, where the separatist Parti Quebecois advocates sovereignty for the French-speaking province. But, he added, "I feel it's time for a new leader to take up this work."

Trudeau's departure marks the end of an era in Canadian politics. He possessed a rare combination of charm, style, intellectual vigor and political skill. A millionaire bachelor when he became prime minister, Trudeau captured the imagination of the Canadian public.

His marriage in 1971 to Margaret Sinclair -- she was more than 30 years his junior -- ended in separation two years ago. Trudeau lives with the couple's three small sons.

It was the question of Canadian unity that brought Trudeau to power. And it was the failure of his approach and the resurgence of separatism in his own province of Quebec that led to his defeat last May.

Some Liberals believed that Trudeau could play a key role in the Quebec referendum as a French-Canadian who devoted his adult life to combating separatism. But other Liberals in Ontario and western Canada have argued privately that the sooner he leaves, the better for the party.

Diplomatic sources said Trudeau had talked privately about discontent within the party and the possible rifts his continued leadership would create. Moreover, after 11 years in power, he was uncomfortable in the role of opposition leader.

His announcement yesterday came as the Liberal Party's national executive committee prepares for a meeting in Ottawa this weekend. The meeting will set the date for the next convention. Trudeau called for a convention in March to choose his successor.

The frontrunners in the race for the Liberal leadership were two English-speaking Canadians, John Turner and Donald MacDonald. Both have served as finance ministers and both currently practice law in Toronto.