Mr Grunshaw said he echoed the thoughts of Avon and Somerset chief constable Andy Marsh, who claimed his force is at ‘tipping point’ after years of government cuts.
He said losing hundreds of police officers over the past seven years has left the force “under incredible pressure”.
Mr Grunshaw said officers are now spending just 20 per cent of their time dealing with crime.
He said: “Part of the reason is the possibly unintended consequences of austerity; cuts to mental health services, cuts to the local authority’s budget including adult social care, children’s social care, and the supporting people budget.
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“The 101 system is being overwhelmed so people are not being able to get through when they need genuine support.”
A Home Office spokesman said: “Crimes traditionally measured by the independent Crime Survey have fallen by well over a third since 2010.
“However, we are sensitive to the pressures the police are under.
“That is why ministers have begun a programme of engagement with forces to better understand the demands they face and
how these can best be managed.”