Canadians will go to the polls to elect a new parliament on 23 January, Prime Minister Paul Martin has announced after losing a no-confidence vote.
Paul Martin's government was unable to shake off earlier scandals
The announcement marks the start of Canada's first wintertime election campaign in a generation.
Mr Martin's government was brought down on Monday night - the first time a Canadian government has fallen on a straight confidence vote.
His minority Liberal government had been in power only 17 months.
Mr Martin said his government had been brought down because "ambition overwhelmed common sense," launching what analysts expect to be a nasty campaign.
Canada's three opposition parties united against his Liberal Party, which has been mired in a corruption scandal.
The right-wing Conservatives, the left-wing New Democrats and the Quebec separatist Bloc Quebecois have very different agendas, but they agreed that they did not want the Liberals to dictate the timing of an election, the BBC's Lee Carter in Toronto says.
Announcing the election date, Mr Martin criticised all three opposition parties individually, but reserved his harshest criticism for the Bloc Quebecois, whom he accused of having "only one ambition, separation".
The French-speaking province will be a key battleground during the campaign, our correspondent says.
Recent polls suggest Mr Martin's Liberals will take most votes in the election - but will not win a majority.
His government has failed to shake off a scandal dating from a previous Liberal administration.
In the late 1990s C$100m ($85m; £50m) of public money was paid by the Liberal government to advertising agencies, for little or no work in return.
It has been alleged that Liberal officials demanded kickbacks for awarding the contracts.
Mr Martin is not implicated in the scandal, but the opposition says he has lost all moral authority.
The prime minister fought off a no-confidence motion in May by a single vote, but lost the support of the New Democrat party earlier this month following a row over private health care spending.
Mr Martin and his government will stay in office until the election is held.
Stephen Harper celebrated after plotting his rival's downfall
Some pundits say the campaign is likely to be bitterly fought, on the evidence of the heated rhetoric flying around in recent weeks.
Conservative leader Stephen Harper accused the Liberals in Quebec of links with organised crime.
The Liberals denounced such "false smears" and threatened to sue.
In the most recent polls the Liberals score about 36%, against 31% for the Conservatives, suggesting the Liberals - in power since1993 - will have to govern with the help of opposition parties.
Canadian governments have been toppled in the past by losing votes on the budget or censure motions, which are interpreted as a loss of confidence - but this is the first time in the country's history a straight no-confidence motion has passed.