The only police forces mutually to agree on a proposed merger have backed out of the plan.
The forces said they felt let down by the government
The Cumbria and Lancashire forces met Police Minister Tony McNulty, but were unable to resolve details of the plan, said the Home Office.
It was the only one of the five mergers proposed by the Home Office to be approved by all the police authorities involved earlier this year.
The Home Office said the forces withdrew after a meeting on Monday.
A joint statement from the forces said the government had not been able to provide a solution to the issue of council tax harmonisation.
Mr McNulty said the government had no other proposals to make and accepted that under these conditions, it would be most unlikely that the merger would now go ahead.
The chair of Lancashire Police Authority, Councillor Malcolm Doherty, said: "We feel badly let down. We have done everything in our power to get this merger to work.
"We now have to find other ways of dealing with the problem that government has left us with."
Chief Constable for Cumbria Michael Baxter said staff in both constabularies had worked hard over recent months towards achieving a successful amalgamation.
"Whilst I am disappointed that amalgamation is now unlikely in the near future, this good work has not been wasted and will be used to improve policing in both areas."
Shadow Police Reform Minister, Nick Herbert, said: "This demonstrates the difficulties of mergers and is the beginning of the end for police force mergers."