Ford, who has long pushed for subways, said he has no reason to doubt that the Ontario Liberals and federal Conservatives aren't serious about pitching in to build the subway in Scarborough.
"I don't see how they can turn their backs on the city," he said. "I just can't see it."
His pet project took a big step forward Wednesday after city council approved a subway, rather than a planned light rail line. But it's not a done deal, as the project is contingent on provincial and federal funding.
The switch will tack on an estimated $1 billion to the $1.4-billion, provincially funded light rail project that was already underway.
The city is asking for all $1.8 billion the provincial Liberals had originally pledged for the light rail project, and for the federal Conservatives to pony up half of the net capital costs. It wants an answer by Sept. 30.
Ford also took the unexpected step earlier this week of saying he was willing to raise taxes to fund the subway.
He wanted to keep it to 0.25 per cent a year starting in 2015, but council voted it down. The city manager has suggested an increase between 1.1 and 2.4 per cent, starting with a 0.5 per cent increase next year.
It's unclear how much money the federal and provincial governments may contribute toward extending the east-west subway to Scarborough.
Ontario Transportation Minister Glen Murray has said that he wouldn't make a final decision until city council made up its mind and provided a sound business plan for a subway.
He wouldn't say Wednesday whether the province will go along with the subway.
"I look forward to tomorrow morning," he tweeted after the vote, alluding to a planned press conference Thursday. "Stay tuned."
A spokeswoman for federal Finance Minister Jim Flaherty did not respond to a request for comment Wednesday.
The federal Conservatives are providing $333 million that's allocated to a separate light rail project along Sheppard Avenue in the city's north end, according to Metrolinx, the provincial transportation authority.
Some had suggested that money could be moved to the subway project, but Murray said that isn't possible.
"We're not redirecting funds from other projects, including Sheppard," he said before the council vote.
If the provincial and federal governments don't provide the money, there won't be a subway, Ford said.
"There is no turning back," he said. "But the fight is not over. It's far from over. We must start making up for lost time immediately to succeed."
Murray, who nixed the idea of a subway two months ago, sparked a new debate last week when he said he was willing to switch from funding light rail to a subway.
The Scarborough light rail project, which would replace an aging rail line, is part of a multibillion-dollar master plan to improve public transit in Toronto, funded mostly by the province.
Metrolinx said it will cost about $925 million extra to extend the subway rather than light rail. It said $85 million has already been spent on the light rail project, including engineering and planning costs.
There are other costs associated with maintaining the existing Scarborough line while the subway is being constructed, estimated to be about $60 million over five years.
Following the council vote, a spokeswoman for Metrolinx would only say that it would consult with the government "to determine next steps."
Toronto Coun. Josh Matlow took to Twitter to voice his discontent with the subway, saying it will lead to higher taxes, deeper debt and a billion-dollar transit fiasco.
"After three long years as mayor, Rob Ford has finally found his gravy train," he tweeted.
The Liberals have denied that their sudden change of heart on the subway had anything to do with the Aug. 1 byelection in a Scarborough riding, one of five Liberal-held seats up for grabs.
But the party has been using it as political ammunition against NDP candidate Adam Giambrone — former chairman of the Toronto Transit Commission — saying he failed to deliver a subway extension to Scarborough.
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