Additional funds are urgently needed to protect older and vulnerable people in the face of £1.1 billion budget cuts to adult social services, a report has warned.
This follows "almost unendurable" cutbacks in the past four years and in real terms could mean people receiving fewer hours of vital home care or less funding for residential care, the Association of Directors of Adult Social Services (ADASS) said.
It warned that some councils have made many of their savings in the past by freezing fees paid to providers, with some £32 million of efficiencies expected to be found through this route in 2016 alone.
This is having a negative effect on staff skills, training, remuneration and satisfaction, it added.
ADASS president Ray James said: "What is at stake is the continuing capacity of adult social care to sustain services to those in greatest need.
"In virtually all our authorities, the number in need is growing, while the complexity of their needs is increasing."
He described expanding NHS budgets at the same time as social care budgets are being reduced as "folly" in the face of the widely-acknowledged significance of the link between the two.
He said health funding has "rightly" been increased from £97.5 billion in 2010/11 to £116.4 billion in 2015/16, an increase of 19.3%.
But over the same period, social care funding has decreased from £14.9 billion to £13.3 billion, a reduction of 10.7%.
“Protecting the NHS is an important policy objective. But the health service itself agrees that an important part of that equation is the simultaneous protection, and enhancement, of social care budgets," he said.
"There is still time for central Government to recognise the jeopardy so many of our citizens are being placed in by the continuing reductions being made to local Government spending.
"Short-changing social care is short-sighted and short-term. It must also be short-lived if we are going to avoid further damage to the lives of older and vulnerable people who often will have no-one else but social care to turn to.
"It is vitally important these care and support services are protected."
Caroline Abrahams, charity director at Age UK, said: "The idea of a billion pounds coming out of social care budgets this year is chilling, given how patchy care quality already is.
"ADASS is not known for hyperbole so when they say further cuts would jeopardise the safety and well-being of vulnerable older people we should take that warning very seriously.
"The service is already pared to the bone with hundreds of thousands of older people with a social care need unable to get any help. We are also hearing of growing numbers of care workers voting with their feet and taking better paid jobs in supermarkets, leading to staff shortages."
Assistant director of policy at think-tank the King's Fund, Richard Humphries, said: "Social care funding was the ghost at the feast of the election campaign, a subject none of the main parties dared to mention.
"Politicians must now be honest about the scale of the pressures on services and recognise that additional funding for social care must be a priority ahead of the Spending Review in the autumn."
A Government spokesman said: "This survey ignores the Government's commitment to put an additional £10 billion by 2020 into health services that are being joined up with social care for the first time, and the contribution of our Better Care Fund, which is already focusing resources on helping people to live independently and improving care closer to home - worth £5.3 billion this year alone.
"We know some councils have managed to make efficiencies at the same time as increasing social care spending - but increasing budgets isn't the only solution. By working innovatively and joining up health and social care we can improve care - and also save money."
Shadow care minister Liz Kendall said: "This Government has failed to address the desperate and growing crisis in older people's care.
"300,000 fewer older people are now getting the crucial help they need than when David Cameron came to power – meaning more older people ending up in hospital and delayed discharges at a record high.
"Cuts of this level would put even more pressure on the NHS, and have a devastating impact on service that are essential to thousands of vulnerable people and their families."