Plans for an ambitious regional police force in the West Midlands have been thrown into disarray after the four existing forces announced they were refusing to co-operate.
They are angry at plans to make them pay the costs setting up the new constabulary, which mean it could start life with debts of up to #42.5 million.
As a result, they are refusing to present by December 23, the deadline set by the Home Office, a detailed business case and formal application to merge.
West Midlands Police, Staffordshire Police and Warwickshire Police are still expected to confirm they support proposals for a new regional force covering five million people.
It would be formed by merging the three constabularies with West Mercia Police, which is fiercely opposed to the plan and wants to remain independent.
However, by failing to present a business case and formal application, they could force Charles Clarke, the Home Secretary, to delay the reforms.
Mr Clarke has the power to authorise any merger which is agreed by all the parties involved, but if he does not obtain their formal consent he must hold another four-month consultation, and present the results to the House of Commons.
The opposition was revealed by Councillor Bob Jones, a member of West Midlands Police Authority and chairman of the national Association of Police Authorities.
Con Jones (Lab), who sits on Wolverhampton Council, is a former chairman of West Midlands Police Authority. He said: "They will not put a formal business case on December 23.
"There will make a submission setting out their opinions, but it will not be the formal submission for voluntary merger which the Home Office was hoping for.
"Almost certainly, the Home Office is going to have to think again."
The figure of #42.5 million was calculated by the four forces in the region.
The APA has estimated the reorganisation will cost between #500 million and #600 million across the country.
Computer systems will have to be re-structured so that merged forces can operate effectively.
Even the re-branding of uniforms, vehicles and police stations will cost millions.
A report by Her Majesty's Inspectorate of Constabulary concluded in September that the current policing structure was unfit for the 21st century.
It said forces with fewer than 4,000 officers - which includes West Mercia, Staffordshire and Warwickshire - lacked the resources to deal with organised crime such as drug and people trafficking, the threat of terrorism and some major murder inquiries.