FRESH doubts have been raised about how Edinburgh's embattled tram scheme will ever be completed - on the day it was originally meant to open.
The German engineering giants charged with building the line have revealed that 72 per cent of the construction work remains with just 38 per cent of the budget left.
In a letter sent to the Scottish Parliament's audit committee, Bilfinger Berger and Siemens also questioned claims made by tram firm TIE that the construction phase of the project would cost just 276 million.
The letter, seen by the Evening News, comes on the day when city council leaders should have been cracking open the Champagne.
According to the project's final business case, which was published in October 2007, the first day the trams were due to be running for paying customers was February 25, 2011.
Instead, the project is now mired in difficulties, with last-ditch mediation talks due to start next month.
The letter from the tram construction consortium notes that more than 150m has already been spent on infrastructure, including various bridges and the Gogar depot, with just over a quarter of the work completed.
It states: "Notwithstanding initial mobilisation payments, how does the residual sum spent to date (150m less mobilisation payments), which represents 28 per cent of the scope, reconcile with the still-to-be-constructed 72 per cent of the scope for the remaining 38 per cent of the budget?"
Published earlier this month, the Audit Scotland report said TIE predicted a total spend of 553m on the project, with a further 32m contingency.
Of that, 267m was allocated for infrastructure works, with TIE saying the figure took into account up-front payments made to the contractor. It added the figure was "heavily dependent" on the dispute with the consortium.
But it is now clear that contractors do not share TIE's optimism that the project can be brought in close to budget, with both utility and infrastructure costs set to rise.
On Wednesday, the council's finance director, Donald McGougan, said he had not ruled out approaching Transport Scotland or the Scottish Futures Trust for more money, despite Finance Secretary John Swinney's repeated insistance that the tram project would receive "not a penny more" of public funding.
John Carson, a former head of maintenance at Network Rail and a long-standing critic of the tram project, said it was unclear if the trams would ever run. He said: "No trams today or any other day in the foreseeable future. TIE has bet the family silver on mediation, a high-risk strategy with little hope of securing a future opening date".All hopes now rest with the mediation talks, which are due to begin next week.
According to TIE, it is only once the talks are concluded that project bosses will have a clear idea of how much of the project they will be able to complete with the money available.
A spokesman said: "Obviously we would have loved nothing more than to cut the opening ribbon on a fully operational trams system for Edinburgh today. However, the reasons why we cannot do so, including the almost doubling of the utility works required and the contractual dispute, are well documented.
"We assure everyone that we are working hard to get back on track and hope to have a way forward following the mediation process." He added: "We are extremely disappointed that we have not had sight of the consortium's letter being referred to. Edinburgh Trams and the City of Edinburgh Council are committed to the spirit of mediation and this is how we intend to enter into the process.
"All of our energy is focused on reaching a positive resolution to the current impasse."
DIFFERENT SIDES OF THE TRACK
Councillor Gordon Mackenzie, city transport convener and member of the tram project board: "There's nobody that's associated with the trams that's not disappointed.
"For a long time it's been quite clear that it would not be possible to have trams running by today's date. But looking forward, the mediation is the best way to break the current impasse.
"If the mediation doesn't work, it would mean we would have thoroughly explored every option other than termination of the contract. That's where logic would tell us it would go."
Councillor Steve Cardownie, deputy council leader and tram critic: "We (the SNP] predicted right from the very outset that this date was a non-starter. Unfortunately, that's proved to be true. We get absolutely no satisfaction from that, though.
"We've not even seen an overhead power line, never mind a tram. I just hope the mediation talks are successful because a lot of public money has been spent on this."