Performance in some parts of the NHS is "completely unacceptable", Health Secretary Jeremy Hunt has acknowledged.
Mr Hunt said there was "no excuse" for some of the problems faced by patients over the winter and accepted that some of the care being offered was not what anyone would want for their own family.
The Health Secretary was speaking after figures emerged showing that numbers of A&E patients seen within the target of four hours fell to a record low of 86% in December, while those waiting longer than 12 hours to be admitted to a hospital bed doubled to more than 2,500 in 2016.
The number of people waiting more than two months to start cancer treatment after an urgent referral was at a record high of 25,157, and the proportion of patients receiving hospital treatment within 18 weeks fell below 90% for the first time since 2011.
Speaking to the BBC, Mr Hunt said there was already a "big transformation programme" under way in the NHS with the aim of treating more people at home or in the community to ease burdens on hospitals.
But he conceded that the changes would take time and said progress had been "disappointingly slow" in some areas.
"It is incredibly frustrating for me," said the Health Secretary. "I am doing this job because I want NHS care to be the safest and best in the world. That kind of care is completely unacceptable. No-one would want it for members of their own family."
He said there were "no excuses" for cases such as 89-year-old Iris Sibley, who was stuck on a hospital ward at Bristol Royal Infirmary for more than six months because a nursing home place could not be found for her.
"It is terrible for Mrs Sibley but it is also very bad for the NHS," Mr Hunt said.
He insisted the Government was addressing problems in the social care system which are preventing many elderly and frail patients from being discharged from hospital - so-called "bed-blocking".
"The Prime Minister has been very clear," said the Health Secretary. "We recognise the pressure's there. We recognise there is a problem about the sustainability of the social care system.
"That has to be addressed and we are going to do that."
Barrister Sir Robert Francis, whose 2013 report uncovered poor care in Mid Staffordshire, said the NHS was facing an "existential crisis" which made a further similar scandal "inevitable".
Sir Robert, a non-executive director at the Care Quality Commission, told the Health Service Journal there was an "increasing disconnect" between what is said nationally about the NHS and "what people on the ground feel or see is going on".
"Let's make no bones about it, the NHS is facing an existential crisis," he said. "The service is running faster and faster to try and keep up and is failing, manifestly failing.
"The danger is that we reach a tipping point; we haven't reached it yet, but there will come a point where public confidence in the service dissipates."
Mr Hunt told the BBC: "What you have to recognise is that overall there are positive things as well as negative things and there is huge commitment in the NHS to sort out these negative things.
"The particular pressure point we have is A&E and what we need to do is find ways of treating particularly people with complex conditions, older people with dementia, at home and in the community.
"It's wrong to suggest to people that these profound challenges such as we face with an ageing population are ones where there is a silver bullet that can solve the problem overnight.
"We have a very good plan that has the support of the NHS. It will take time to deliver, but in terms of immediate support we are doing what we can with extra financial support in the NHS this year - more doctors, more nurses.
"We also need to row in behind people in the NHS who are working very hard to try to solve these problems. And we also need the public's help, because we know that a number of the people who are seen in A&E could actually have their needs dealt with in another part of the NHS.
"We need to make sure that as far as we can we free up people in A&E departments to deal with the most vulnerable older patients who have particular needs."
Asked whether there would be more money for the NHS in the Budget, Mr Hunt said: "That is for the Chancellor and Prime Minister, but look at what the Prime Minister said this week: This is an area where there is pressure and if we are going to have a solution, it needs to be a long-term and sustainable solution and not a quick fix."