Ed Miliband is risking all-out war with the Labour leaders of big cities in the North and Midlands if he continues to put out a “a negative message” over the planned high speed rail line, the leader of Birmingham City Council has warned.

Sir Albert Bore, Labour leader of the nation's largest local authority, said Mr Miliband risked “a protracted public conflict” with his own party in the run up to the 2015 General Election, in a blunt letter written on behalf of the eight biggest cities outside London.

He is the transport spokesman for the Core Cities Group, which includes Birmingham, Bristol, Leeds, Liverpool, Manchester, Newcastle, Nottingham and Sheffield.

Writing on behalf of all the cities, Sir Albert expressed anger over the decision of the party leadership in London to perform a U-turn over the project.

Gordon Brown’s government announced it was committed to building a new high speed rail line linking London, Birmingham and Manchester in 2010.

But Labour now says it is not convinced the new line known as HS2 should be built - even if costs don’t rise any higher than the current budget of £42.2 billion, which includes 28.2 billion for the line and £14.4 billion in contingency funding.

In a letter to Shadow Transport Secretary Mary Creagh, Sir Albert said: “If the party continues to put out such a negative message on HS2 I will be concerned that there will be a protracted public conflict between the party leadership and the Labour led core cities at a time when we should be working closely together to develop a winning campaign for 2015.”

Cities are ready to fight back over HS2, Birmingham Council leader Sir Albert Bore has warned
Cities are ready to fight back over HS2, Birmingham Council leader Sir Albert Bore has warned
 

Referring to Mr Miliband’s “One Nation Labour” slogan, Sir Albert said: “It is a One Nation investment project and must be at the heart of Labour’s manifesto for 2015.”

And he warned that Labour had to return to backing HS2 now - because work to ensure major cities enjoyed economic benefits from the scheme is already underway.

He said: “HS2 is the single most important infrastructure project currently planned in terms of bringing growth and jobs to all the city regions – their core cities as well as the surrounding towns and cities - and rebalancing our economy away from London and the South East.”

He added: “All of the core cities are working hard to develop investment plans that will link up the whole of their city regions to HS2 when it arrives and ensure that maximum value is achieved from the  project.

“Planning is underway for new stations and for the regeneration that will take place around them and at other sites. Private sector investment is already being levered even before construction has begun.”

Hitting out at Labour Shadow Chancellor Ed Balls - who unexpectedly announced during Labour’s conference in September that the party was reconsidering support for the project - Sir Albert told Ms Creagh: “I have to say that recent messages from senior Labour politicians have not helped our cause at all.

"The press release put out in your name yesterday contained very similar words to those used by Ed Balls in his speech in Brighton and appeared to signal a significant weakening of the party’s commitment to the project.

“Of course it is important  for oppositions to hold governments to account on how they deliver large projects. But the  scale of HS2 means it must continue to have the cross-party support it has enjoyed to date  and it is important that the party does not end up boosting the opposition to the project by appearing to question its value very publicly.”

Shadow Chancellor Ed Balls says he is not convinced of the case for HS2
Shadow Chancellor Ed Balls says he is not convinced of the case for HS2
 

Other big city leaders have also written separately to Ms Creagh. Nick Forbes, the Labour leader of Newcastle City Council, told her: “In the Core Cities we are already doing our bit but councils and businesses need to move  forward with confidence in the future of HS2.

"So, I urge you to give the clearest commitment that we can all plan for future, sustainable growth supported by HS2 and wider transport investment.”

The Department for Transport and rail industry experts warn that the existing rail network, an in particular the East Coast Main Line and West Coast Main Line, cannot cope with growing demand for rail travel.

A new paper published by the Department for Transport setting out the case for HS2 said: “The West Coast Main Line is under stress because there is more demand for train services than there are train paths available.

"This not only limits overall capacity, but means there are trade-offs about deciding which services can run.”

Defending Labour’s stance, Shadow Chancellor Ed Balls admitted in a BBC interview that Labour could leave local authorities waiting for “months” for certainty.

He said: “Well my job as the Shadow Chancellor and potential Chancellor at the next election is to be hard-headed about standing up for value for money for taxpayers and the government has produced its fifth report on the benefits today, changing the numbers again.

“I’m not going to say within an hour whether we are persuaded by these, that would be completely irresponsible, that is the kind of flibbertigibbet Treasury which we are seeing at the moment from George Osborne.

“We will study the details of this in the coming weeks and months. It has got to stack up, the costs have got to be under control.”

The Taxpayers’ Alliance said the report was “another attempt by the Government to make the numbers behind HS2 stack up”.

And Stop HS2 campaign manager Joe Rukin said: “As we expected, the Government have pulled some random figures out of the air in a desperate attempt to con the public.”

But business leaders in Birmingham insisted HS2 was “the only long-term solution to Britain’s future transport needs”.

Jerry Blackett, chief executive of Greater Birmingham Chambers of Commerce, said: “The alternative to HS2 of upgrading the existing line has already been estimated to cost £20 billion with associated delays to allow the work to take place amounting to the equivalent of 14 years of weekend route closures.”

City MP Andrew Mitchell (Con Sutton Coldfield) said: “It is disappointing that the Labour Party continues to send out confusing messages nationally about how they view HS2. We need cross party support for the scheme to work.”

Read Sir Albert Bore's letter in full here