A merger of Midland police forces could be challenged in the courts, after the Home Secretary appeared to suggest he had already decided to create a huge regional constabulary.
Charles Clarke described a merger of West Midlands, West Mercia, Staffordshire and Warwickshire Police as "the sensible proposals".
Speaking in the House of Commons, he suggested he was determined objections from critics would not be allowed to stop the merger going ahead.
But officially, the Government is obliged to hold a three-month consultation.
Because West Mercia Police is fiercely opposed to the merger, this is likely to happen.
The chair of West Mercia Police Authority and the force's Chief Constable are to meet Home Office Minister Hazel Blears today to confirm their opposition to the plans.
MP Peter Luff (Con Mid-Worcestershire), who has campaigned against the merger, said: "Charles Clarke has let the cat out of the bag.
"It seems to me that this could lead to a legal challenge or judicial review, because we are supposed to have a genuine consultation but it seems he has made up his mind."
Warwickshire, Stafford-shire and West Midlands Police all back the creation of a regional "strategic force" which would serve five million people.
West Mercia opposes the plan and wishes to remain independent.
Speaking in the Commons, Wolverhampton MP Rob Marris (Lab Wolverhampton South West) asked how a merger would affect the police precept, which is added on to council tax bills to pay for local services.
Mr Clarke told him: "As he knows, three of the four forces in the West Midlands region favour this amalgamation.
"There are issues, as he rightly says, about the precept and how it can be brought together effectively.
"That is precisely one of the issues on which the forces themselves have made proposals and which we will discuss with them.
"I can assure him that we will come to a sensible conclusion in that regard, but we will not allow that to present a blockage to the sensible proposals supported by three out of four forces in the West Midlands."
The Home Office is reforming England's police services after an independent review concluded smaller forces lacked the resources to deal with terrorism, organised crime and other major issues.