Today's "drop-dead date" on the project, when the tram cars are due to be ordered from manufacturer Bombardier, will pass without agreement.
Those backing Merseytram believe the last few days have proved "positive" but their financial deal has still not been accepted by the five local councils.
As well as the obvious regeneration benefits which will be lost if Merseytram collapses, today the Daily Post can reveal for the first time the stark financial facts facing the scheme.
As the local councils waver over their support, the cost of bringing Merseytram to this point already stands at £30m, including:
* Millions of pounds to order the 11 miles of steel track needed for Line One;
* Up to £15m for the diversion of underground utility pipes, half of which have already been completed or scheduled;
* Huge legal fees for last year's lengthy public inquiry and other negotiations including compulsory purchase orders;
* £50,000 a week to keep the private M-Pact consortium (due to build and run the tram) together while its future hangs in the balance.
Merseytravel director general Neil Scales pre-ordered much of the work to keep the tram on schedule for completion before Capital of Culture year in 2008.