A review of policing in England and Wales by the National Audit Office (NAO) has highlighted huge falls in police staffing levels and reductions in the percentage of crimes which result in criminal charges.

The spending watchdog warned of “stress” in the system as forces struggle to carry out proactive policing work to tackle offences like drug trafficking and drink driving. Since 2010, funding and staffing levels have fallen, while police are confronting rising levels of recorded “high harm” crimes and a heightened terror threat, the NAO said.

It warned that the Home Office’s “light touch” approach means it does not know if the police system is financially sustainable.

Sir Amyas Morse, Head of the NAO, said: “There are signs that forces are already experiencing financial strain and struggling to deliver effective services to the public.

“If the Home Office does not understand what is going on it will not be able to direct resources to where they are needed, with the risk that the situation could get worse.”

The review found that the time it took to charge an offence increased from 14 days for the year ending March 2016 to 18 days for the year ending March 2018.

The proportion of crimes which resulted in a charge or summons fell from 15 per cent in March 2015 to nine per cent in March 2018.

Overall funding to forces - a combination of central government grants and council tax - has fallen by 19 per cent in real terms since 2010-11, according to the NAO.

Police force are balancing their books by reducing the size of their workforces, the report said, citing falls of 40 per cent, 21 per cent, and 15 per cent in the numbers of PCSOs, police staff and officers respectively between 2010 and 2018. The NAO disclosed that in November an internal Home Office report concluded that forces were facing increased pressure in meeting demand for police services.

“While the department assessed that pressure is currently at a manageable level, it identified a number of forces that were high-risk in terms of future resilience,” the watchdog said.

Plans to reform “ineffective” arrangements for allocating police funding are on hold, the NAO said, adding: “We cannot conclude that the Home Office’s oversight of the police system is value for money.”

A Home Office spokesman said: “Our decision to empower locally-accountable Police and Crime Commissioners to make decisions using their local expertise does not mean that we do not understand the demands on police forces.

“In addition, the report does not recognise the strengths of PCCs and Chief Constables leading on day-to-day policing matters, including on financial sustainability.

“We remain committed to working closely with police and delivered a £460m increase in overall police funding in 2018/19, including increased funding for local policing through Council Tax.”

Meg Hillier, who chairs the Commons Public Accounts Committee, urged the Home Office to “get a grip” on police funding.

Police forces '˜struggling to deliver services', National Audit Office review finds