Edinburgh Council has been urged to clarify the project budget
Fresh funding concerns have been raised over the future of Edinburgh's trams project, after a multi-million pound extension to the network was shelved.
Edinburgh City Council has been urged to spell out the budget for the trams project amid fears of a cost overrun.
BBC Scotland news website revealed how the spur line, known as 1b, from Haymarket to Granton has been ditched because of the economic downturn.
The line was planned to service new developments at the city's Waterfront.
Nationalist Lothians MSP Shirley-Anne Somerville raised questions over the funding of the main line, known as 1a, from the west of the city through to Newhaven.
She told BBC Radio Scotland: "I'm very concerned about the information we're getting."
It has been known for "some months" that the spur line line is "dead", according to Ms Somerville.
The MSP added: "Now what we need to see is some clear information coming out on 1a.
"It's very difficult for any of us to believe that this is going to be built on time and on budget.
"Tie have a responsibility to come forward and give us a very detailed updated business case to prove to the city of Edinburgh how that's actually going to be possible."
The main tram route, line 1a (red line), is being built, but line 1b (blue line) from Haymarket to Granton has been dropped
Transport Initiatives Edinburgh (Tie) is the arms length firm set up by the council to manage the trams scheme.
The minority SNP Government at Holyrood wanted to ditch the project, initially priced at about £500m, soon after coming to power in 2007, but agreed to press ahead after losing a vote on the issue in parliament.
Tory Lothians MSP Gavin Brown told the programme the spur line was latest victim of "Labour's recession".
He added: "In relation to 1a I think we need to see very quickly where the money is coming from.
"Some of it was going to have to come from developers' contributions and additionally in terms of looking at the contracts, if 1b were not to go ahead, apparently 1a would increase by £6m because the two were negotiated together.
"Where is that money coming from? The council need to really do their homework pretty quickly, give us the figures as soon as possible to give the public a bit of confidence."
The trams project was at the centre of an angry dispute earlier this year between project bosses and their contractors, which saw work halting on the Princes Street stretch of the scheme.
Dave Anderson, Edinburgh City Council city development director, said: "The business case for 1b was initially formed several years ago and at that time we expected to see the expansion of about 30,000 homes in Edinburgh's Waterfront over 20 years.
"Clearly that's been impacted by the global recession so we have decided the most sensible course of action is to postpone the development of line 1b at this stage."
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