A police authority threatened the Home Secretary with High Court action yesterday over force amalgamations. 

Cleveland Police Authority, which has the backing of its force, said it was seeking a judicial review of the decision by Charles Clarke to merge it with the Durham and Northumbria forces.

Northumbria and Durham have agreed on the regional force proposal but Cleveland is strongly against, favouring a two-force alternative, in which it and Northumbria would split Durham between them. Durham, in particular, opposes the Cleveland idea.

The authority has given Mr Clarke until Thursday to withdraw merger proposals on the grounds that they are "irrational and perverse and have been taken after a process conducted with undue haste".

The authority also argues that "wholly insufficient time" has been allowed to evaluate alternative options, including its preferred option - a Tees Valley force comprising Cleveland and south Durham.

The Home Office said last night that the judicial review threat was "premature."

The Cleveland letter urges the Home Secretary to allow 12 months of evaluation. This month, Mr Clarke announced the start of a four-month consultation, required under the 1996 Police Act, for the North East and other proposed amalgamations.

The Cleveland action will be monitored in other regions where there is hostility to mergers and legal action is a possibility.

These include Cheshire, which is unhappy about a proposed merger with Merseyside, and Cambridgeshire, which opposes an East Anglian force.