The head of Toronto's unionized outside workers has raised the spectre of a lockout in early January as the city mulls plans to reduce its workforce.

"The writing is on the wall. We're already hearing rumours of lockouts at the corridors of City Hall and we're preparing for that eventuality," Mark Ferguson, president of CUPE Local 416, told CTV News on Wednesday.

However, Ann Dembinsky -- president of Local 79, which represents inside workers -- wouldn't speculate on the possibility of a lockout.

Mayor Rob Ford wouldn't comment on camera, but his staff told CTV News that any lockout talk was news to them.

The city's contract with its unionized workforce expires on December 31. That deal was reached following a 39-day strike in the summer of 2009.

Local 416 represents about 6,700 outside workers while Local 79 represents about 18,000 inside workers.

New contract talks come as the city grapples with a huge budget hole.

On Tuesday, the city announced it was offering a voluntary buyout program to both workers and management. TTC workers, library staff and police are not eligible, although the Toronto Police Services Board has offered buyouts to senior ranking officers.

Up to 17,000 city employees are eligible for Tuesday's offer, which caps payment at six months’ pay. The city hasn't been specific about how many departures are needed or given a specific cost reduction target.

City officials have said that if the needed cost savings can't be achieved through buyouts, then layoffs will be used.

Ford, who won by a comfortable margin last fall on a campaign of "stopping the gravy train," told reporters the city's labour force is too large.

"We have too many employees down at City Hall. We have to find ways of giving them packages to move on, or entice them to move on. We just can't carry 53,000 employees anymore," he said Tuesday.

Ford is keen to replace city workers by contracting out service delivery to the private sector where possible. He plans to start with some garbage collection.

The city is facing a shortfall of $774 million as it heads into its 2012 budget year. It is currently receiving a series of reports from consulting firm KPMG on what services could be reduced.

Ford guaranteed during the municipal election campaign there would be no service cuts. He promised to cut labour costs through attrition. In his first budget, he froze property taxes and eliminated the $60 vehicle registration tax.

Ferguson said all these issues mean the bargaining for a new contract will be difficult.

"When this administration is bent on attacking services and taking those services away from the public," his union is forced to defend those services, he said.

Ferguson said he's been seeking a meeting with Ford since January with no success.

Dembinsky said she also hasn't met yet with Ford.

"We have never had a single conversation with the mayor about finding efficiencies," she said. "He's on a witch-hunt looking for gravy that just isn't there."

With a report from CTV Toronto's Naomi Parness