The timing is suspicious, given that a Scarborough riding is among five Liberal-held seats that are in play in Aug. 1 byelections, the opposition parties said.
Metrolinx, Ontario's transportation agency, is already on track to replace the current surface rail in Scarborough with light rail with $1.8 billion set aside by the province, as part of a multi-billion-dollar master plan for Toronto transit.
Transportation Minister Glen Murray said in May that he wouldn't amend the transportation blueprint again — as the Liberals did in 2011 — to extend the subway line.
But he changed his tune Thursday, leaving the door open to talks on the subway.
"I have said over my dead body will people in Scarborough be left out of transit," he said. "We have a plan. I'm really not fussed about whether it's a subway or an LRT."
Murray said he's not negotiating a deal with the city right now — contrary to published reports — and isn't making any immediate commitments.
City council must make up its mind by July 16, he said. If it finally settles on a subway, he'll have a "serious conversation" with council, but the final decision will rest with the province, Murray said.
It's interesting that he's backtracking on the subway now that a Scarborough seat is up for grabs, said Progressive Conservative Lisa MacLeod.
Tory Leader Tim Hudak has been vocal about his support for subways, and the Liberals are now nervous that his plan is more popular, she said.
"While I think it's interesting that Mr. Murray is now climbing down, I don't think that his intentions are exactly being made from the bottom of his heart," she said.
Murray denied it had anything to do with the byelection. But the Liberal party was quick to slam NDP candidate Adam Giambrone — former chairman of the Toronto Transit Commission — for failing to deliver a subway extension to Scarborough.
"Only the Ontario Liberals have serious plans to improve transit for all Scarborough residents," Liberal candidate Mitzie Hunter said in a statement.
The governing Liberals are already under fire for the politically-motivated cancellations of two gas plants in the Toronto area, one of which was nixed during the 2011 election campaign.
"Once again the Liberals are proving that they'll say anything and do anything to win elections and hold onto power," NDP Leader Andrea Horwath said in a statement.
But the subway extension may also be a bargaining chip in the province's dispute with Toronto Mayor Ford over new levies to pay for public transit in the Greater Toronto and Hamilton Area.
Premier Kathleen Wynne has made it one of her top priorities, but Ford has refused to entertain any of the options to raise the $2 billion a year the province said is needed to relieve congestion, including a one per cent hike of the harmonized sales tax.
The tax-averse mayor has been pushing for the subway extension, however, which Metrolinx estimates will cost an additional $925 million.
The extension could help make the case for new levies, said Karen Stintz, chairwoman of the Toronto Transit Commission.
"There's no question that if people are seeing value for the infrastructure that's being built, it puts us in a better place to ask them to invest in that project," she said.
Murray insists the city must give him a business plan if it wants the subway extension, and is calling on the federal Conservatives to step up and cover one-third of the costs.
The extension could qualify for federal funding since it would be considered a new project, said Stintz.
"Subways don't get built for free," she said.
"But if we can get the $1.8-billion commitment from the province, if we can get a contribution from the federal government, then we'll be in a better position to know what the city's contribution looks like."
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