MERSEYTRAVEL last night accused Liverpool city council of jeopardising the entire three-line Merseytram project.
It is the latest twist in a continuing bitter battle between the two organisations over the return of trams to the region.
The passenger transport authority is furious about the city's demand that Line Two of Merseytram should go to Liverpool John Lennon Airport.
It is currently due to open in 2008 linking Liverpool city centre with Prescot and Whiston hospital, with JLA being served by Line Three two years later.
But, last Friday, Liverpool's cabinet demanded a change in the timetable to accelerate the airport route.
A meeting of the Merseytram committee yesterday passed a resolution condemning the council and expressing "grave concerns" at its actions.
It said the council had "jeopardised the delivery of the Merseytram scheme" on a number of levels.
"It has undermined the support of the private sector, the Department for Transport, Her Majesty's Treasury, national, regional and local stakeholders, and the Merseyside public for the three line Merseytram network," it said.
The committee said the council had ignored the policies agreed by the five Merseyside authorities in the Local Transport Plan and risked "losing multi million pounds worth of savings made by constructing the first two lines of the Merseytram network in parallel."
The council's plan of using a route to JLA through Belle Vale, Halewood and Garston using the old loop line was similarly condemned.
The committee warned the council's actions could lead to funding for Merseyside being lost to other areas and ignored the negative impact it would have on Knowsley.