Jeremy Hunt has warned the NHS that it is unlikely to get a significant boost to its budget in George Osborne’s forthcoming spending review, but hinted that ministers have recognised that additional cuts to social care would only put further strain on frontline health services.

Speaking to an audience of 500 NHS bosses, the health secretary sought to lower expectations that the chancellor will be able to hand the NHS a sizeable downpayment on the £8bn the government has sought to provide by 2020 in his autumn statement on 25 November.

Hunt stressed that the unprecedentedly tough financial situation left the Treasury little scope to be generous to the NHS.

“The spending review will be the most difficult spending review in a generation and possibly in the history of the NHS. This is a very, very challenging financial situation for the government and for the chancellor,” Hunt told the NHS Providers’ annual conference in Birmingham.

This week Simon Stevens, the chief executive of NHS England, went public with his concern over negotiations with the Treasury before the spending review.

“As of today, considerably more progress is going to be needed before we can say we have a genuinely workable NHS funding solution for 2016-17 and 2017-18, but spending reviews usually come down to the wire, so hopefully we’ll get there by 25 November,” Stevens told the Health Service Journal on Monday.

Stevens is understood to want much of the £8bn to be frontloaded – that is, several billions of it to be provided upfront in the spending review – so that the NHS can press on with long-promised work to deliver how care is delivered as part of a plan to save money. However, well-placed NHS sources say the Treasury is not persuaded by that argument and may give Stevens much less than he is seeking.

Hunt said every government department was having to adjust to the continuity policy of reducing overall Whitehall spending. Departments including transport, environment and communities and local government have already agreed to deep cuts in their budgets.

However, Hunt dropped what NHS Providers and some delegates interpreted as a clear hint that spending on social care could ultimately become ringfenced, in the same way that – unlike most government departments – the NHS’s income has been since 2010. It was his personal view, he said, that policy needed to evolve to ensure a “trajectory where social care is protected”.

Chris Hopson, the NHS Providers chief executive, said earlier that “when social care is cut, the NHS bleeds”. Hunt, in his most public signal yet of accepting that argument, said ministers including the chancellor recognised that health and social care, despite being run by separate organisations (the NHS and local councils), were interdependent.

He said he appreciated that events in the social care system had a direct impact on the number of people turning up at A&E units, and stressed the importance of councils being able to provide effective domiciliary care services to mainly older people in order to reduce the risk of them ending up in hospital.

The health secretary insisted again that the NHS needed to make the £22bn of efficiency savings that Stevens last year committed the service to delivering by 2020 when he launched his five-year Forward View blueprint to secure the service’s long-term future as a taxpayer-funded service.

When asked about his view of the NHS’s future, given the growing pressures placed on it from an ageing and growing population, Hunt said he was “cautiously optimistic”.

Hunt defended the £200m cut to public health budgets in England this year as being part of the NHS-wide drive to meet the £22bn target by 2020. He said good progress had been made in recent years on key public health issues such as reductions in the number of teenage pregnancies and teenagers who smoke. All parts of the NHS had to make savings over the next few years, he said. That will mean a 6.2% cut in the amount of money local councils receive for public health activities in 2015-16.

The move has been widely criticised by doctors, public health experts and health charities who say it is likely to set back efforts to tackle the growing burden of ill-health through better prevention. Some believe it is likely to prove counter-productive by adding to the growing pressures on frontline NHS services.

Hunt again defended his decision to impose an unpopular new contract on the 45,000 junior doctors working in the NHS in England , saying he was “doing the right thing” by seeking to ensure that more of them work more often at weekends as part of the government’s drive to create a seven-day NHS by 2020.