TORONTO -- A group representing the mayors of Canada's largest municipalities says the Ontario government's move to invoke a constitutional provision to push through legislation slashing the size of Toronto city council is unprecedented.

The Federation of Canadian Municipalities says it is throwing its support behind Toronto in the city's fight against the province's actions.

The group's Big City Mayors' Caucus Chair, Doug Iveson, says Premier Doug Ford's moves have now placed Canadians in a constitutional debate when the limits of how governments can work together within the document have not been tested.

The group's comments come as Toronto politicians hold an emergency meeting today to discuss their next steps.

Mayor John Tory says the province's actions are "wrong and unacceptable."

The city had challenged the province's council-cutting legislation in court and a Toronto judge agreed earlier this week that passing the bill in the middle of municipal election campaign violated the freedom of expression rights for voters and candidates.

Ford, however, quickly announced he'd take the unprecedented step of invoking the notwithstanding clause to override the ruling, and the government reintroduced the council-cutting legislation yesterday.

The premier says using the clause is necessary to ensure the will of elected politicians trumps the court ruling.

The province's council-cutting legislation would reduce the number of Toronto's wards to 25 from 47, with the city's election set to take place Oct. 22.

The opposition parties have vowed to use procedural tools to delay the bill as much as possible.