MERSEYTRAVEL is considering calling in the district auditor to investigate what it claims is the "obvious bias" in a report by council treasurers into the future of the Merseytram project.
Senior officials at Hatton Garden are furious they were not given the chance to question the report - written by the treasurers of the five Merseyside councils - before it was made public.
The passenger transport authority roundly rejects much of the contents of the report, details of which were leaked in the Daily Post on Saturday.
It revealed how the cost of Merseytram might lead to an extra £6.5m on the council tax levy by 2009/10 and how contributions to the repairs budget for the Mersey tunnels might be reduced to help pay off the loans.
Both suggestions are rejected by Merseytravel but the report was enough for Sefton and St Helens councils to declare the finances "unacceptable".
Tram supporter Knowsley has also said the tram must not impact on council taxpayers.
Last night, a senior Merseytravel source claimed: "This report is a total stitch-up. We were only allowed to see it half an hour before the last meeting of leaders and chief executives on September 9. It was agreed nothing would be done until we had the chance to comment because we disagreed with a lot of what was in it.
"We are now considering asking the district auditor to investigate what we believe is the obvious bias of the report.
"It takes no account of the social benefits of Merseytram at all. Merseytravel has said that there will be no impact on the levy at all for the foreseeable future."
Last night, Merseytravel declined to comment officially on the revelations but there is no doubt the gloves are now firmly off in the battle to either build Line One or pull the plug.