THE Tories have refused to commit to delivering the £250m Leeds trolleybus plan should David Cameron win the forthcoming election.
A Conservative source said the party would not follow Labour's lead and protect the scheme from future spending cuts by effectively ring-fencing its funding.
The source said: "We are not committed to it, basically. Whilst we appreciate the importance of projects like this, we are not going to make election promises."
Transport minister Sadiq Khan announced on Monday that the Department for Transport (DfT) had given "programme entry approval" for the trolleybus scheme and will contribute 235m towards its 254m cost.
The trolleybus, powered by overhead electric cables, would run north through Headingley to Holt Park and south to Stourton via Clarence Dock and Hunslet.
Government officials rejected council and Metro pleas for funding for a city centre loop and a line to St James's Hospital.
Questions have, however, been raised about the timing of his announcement, just weeks before a General Election in which Labour is desperate to hold onto to a string of marginal West Yorkshire constituencies.
The Conservative's shadow transport secretary Theresa Villiers has raised questions about how the project will be funded, saying: "Labour need to be straight with people about how they are going to pay for their pre-election giveaways."
Deep cuts are expected in the Department for Transport's budget after next year, as which ever party forms the next government attempts to reduce the huge deficit.
Mr Khan this week pledged that the trolleybus scheme - known as New Generation Transport - will not fall victim to spending cuts if Labour wins.
But the Tory source said: "The public finances are in such a terrible state we will have to review everything if and when we get elected."
Coun Andrew Carter, the Tory joint leader of Leeds Council, said: "I am not surprised they want to keep their options open. What everyone seems to have forgotten is that the rider from DfT says this doesn't commit government to giving us the money. All it does is give the scheme programme entry."