Commuters in Canada's biggest city may find themselves stranded early Monday morning as Toronto transit workers are planning to go on strike.

"Most of you are working people like us. It is therefore with the deepest regret that we will be withdrawing our services as of Monday morning," Bob Kinnear, president of Amalgamated Transit Union Local 113, said at a news conference on Friday.

He said workers would be walking off the job because the latest contract offer from the Toronto Transit Commission is "inadequate."

"We will give the Commission the weekend to think about the consequences of their inadequate offer," Kinnear said after the TTC and the union failed to reach a deal by the Friday noon deadline.

"I am deeply, deeply disappointed," TTC chairman Howard Moscoe said in response.

"We moved heaven and hell to present the best offer we could possibly present under the circumstances."

Moscoe added that negotiations were not over as far as the TTC was concerned.

"I am prepared to continue discussions around the clock until we put this to bed," Moscoe said.

Toronto Mayor David Miller called on the two sides to return to the bargaining table.

"A transit strike in Toronto is in no one's interest, it's a very serious step," he told reporters. "Our economy depends on the Toronto Transit Commission."

If necessary, he said, he will intervene. But not yet.

"You have to allow your negotiators to negotiate. You can't become the negotiator. I will step in when the timing is right for me to step in."

Miller said his first step will be to speak to Ontario Premier Dalton McGuinty over the weekend to discuss the options, one of which is back-to-work legislation.

But McGuinty isn't offering Toronto commuters any assurances his government will step in to end a strike. He says the two sides still have time to reach an agreement and he's going to wait and see what happens over the weekend.

If the union follows through with Monday's strike, more than 8,000 bus, subway and streetcar workers will be off the job.

Last month, 99 per cent of union members voted against a five-year offer that included a two per cent wage increase in each of the next three years.

Moscoe said Friday that the new offer was an increase of 2.75 per cent in the first year, 3 per cent in the second year, 3.25 per cent in the third year and the increase in the fourth year had yet to be negotiated.

The union has also said it wants to see an increase of pension contributions and scheduling flexibility, while the transit commission says it needs funding from all three levels of government.

Also at issue is language in the contract that allows for some work to be contracted out. The TTC has said that they don't have the intention to contract out work.

About 1.4 million passengers use Toronto's transit system on a daily basis.

When the city's transit workers last went on strike in 1999, the city's highways and roads were clogged for two days as transit riders were left scrambling to find new ways of reaching their destinations.

Meanwhile, the Toronto Board of Trade called on businesses to work in tandem with their employees to cope with the planned strike.

"Businesses should be trying to make it easier for employees to get to work or to work from home," Board President Glen Grunwald said in a statement.

"And employees should be making alternative arrangements to get to their jobs. Both groups need each other's help to cope with the difficulties this strike will create."

The Board suggests: employee car pools, more parking or bicycle storage space, or working from home where possible.

The Board is predicting that a strike will reduce productivity at all businesses in the city, therefore impacting the economy.

With files from The Canadian Press