Crime tsars have threatened the Government with legal action over further police funding cuts, according to reports.
Seven police and crime commissioners, who were elected for the first time in 2012, have written to policing minister Mike Penning urging him to delay a decision on force budgets expected in the Government's spending review this month.
The changes to the police funding formula will result in cuts that are "unfair, unjustified and deeply flawed", they said in a letter seen by the Independent.
Their intervention comes after senior police officers warned of safety fears as front-line services could be affected by further cuts, while the Home Secretary Theresa May has insisted forces can be more efficient.
According to the paper, the letter said: "We believe this process should be halted immediately and the process redesigned to five forces and commissioners the information and time they need to make a proper and fair assessment of its consequences.
"It is with much regret that we are therefore taking legal advice with a view to initiating a judicial review, should our concerns not be addressed."
Stephen Greenhalgh, London's deputy mayor for policing and crime, has signed the letter along with the commissioners of the Cumbria, Lancashire, Devon and Cornwall, Merseyside, North Yorkshire and Thames Valley forces, the paper added.
Mr Penning, upon announcing plans to change the police funding formula in July, said the current model was "complex, opaque and out of date".
He said: "Police reform is working. Over the last five years, front-line services have been protected, public confidence in the police has gone up and crime has fallen by more than a quarter, according to the independent Crime Survey for England and Wales.
"However, if we want policing in this country to be the best it can be, then we must reform further, and that includes putting police funding on a long-term, sustainable footing."
Chancellor George Osborne has asked ministers in non-protected departments - such as the Home Office - to come up with reductions in their budgets of between 25% and 40% by 2019/20 ahead of the Comprehensive Spending Review (CSR) on November 25, when the Government's plans for the next four years will be set out.
Metropolitan Police commissioner Sir Bernard Hogan-Howe has previously said he is worried for the safety of London if the Chancellor announces cuts of £800 million or more over the next four years, while Lancashire's chief constable Steve Finnigan warned that expected budget reductions of £60 million will mean his force will "not be viable as we see it today" by 2020.