CONSERVATIVES on Edinburgh Council are to call for a city-wide referendum on whether the controversial extension to the capital’s tram line should be built.

The £162 million extension of the line from the city centre to Newhaven is set to be delayed in any case. The Capital Coalition of Labour-SNP councillors has accepted that there must be a delay for further investigation and financing of the extension, though land purchases for the eventual extension may continue.

The National can reveal it was fierce opposition from SNP councillors that has forced council leaders to agree to an indefinite delay to the project which was given approval in principle last month and which would have been funded by an extraordinary dividend of £25 million from the council-owned Lothian Buses.

A final decision had been delayed until next week’s council meeting for greater scrutiny of the business case – described by one councillor as “deeply flawed” – for the extension, and SNP councillors concluded earlier this week that it was “as flawed as the original business case for the trams all those years ago,” according to one member.

The eight-strong group of Labour and SNP councillors charged with examining the issue had been forced to recommend delay, said a council source, largely because the business case was seen as too optimistic, while the opposition of Lothian Buses’ drivers through the Unite trade union had also been a factor.

An SNP source said: “The business case just didn’t stack up. It actually begged even more questions than it answered.”

The National can also reveal that even as the business case was being prepared for last month’s council meeting, council officials were speaking to suppliers in the industry to discuss cheaper ways of building the extension.

James Harkins of the Light Rail (UK) secretariat confirmed to the National that potential suppliers had been contacted.

He said: “There are cheaper tram construction equipment and methodologies, such as not moving the utilities but stopping the trams and giving access, top slicing as used by Manchester Metrolink, to name but a few.”

The proposal for a referendum will be controversial in

Edinburgh because just over 10 years ago, the council organised a referendum on the proposed congestion charge for the city, and it was defeated – on a 61 per cent turnout, three-quarters of those who voted rejected the charge.

It was that decisive vote which caused a lot of financial trouble for the trams – the proceeds from the charge were supposed to help pay for the tram network, originally planned for three lines but eventually involving only one.

Leading the call for a referendum to be held on the same day as the council elections in 2017 is Councillor Nick Cook, the transport spokesman for Edinburgh’s Conservatives.

He said: “No matter when they bring the proposal forward, it is going to be controversial and we believe it is a significant enough issue to warrant a public ballot.

Conservatives remain clear that the current proposals are deeply flawed – they are too expensive and would take too long. They rely too heavily on assumption and there is a huge question-mark over the council’s ability to manage a project of this scale.

However, if the majority of councillors are intent on pressing ahead with such a divisive project, despite the weight of concerns and the major risk to which the council would be exposed, then the reports and business case presented should be tested in the court of public opinion.”