David Cameron and Nick Clegg pledged today to listen to concerns about NHS reforms but warned "no change is not an option".
Launching the Government's listening exercise on the Health and Social Care Bill, the Prime Minister stressed the NHS was the nation's most precious asset.
But he admitted the Government had been "charging ahead" with the reforms and must now pause to address worries coming from many quarters, including patient groups, Royal Colleges and unions.
The Deputy Prime Minister accepted it was an "unusual" move to launch a listening exercise when the Bill had already passed its Commons committee stage but said it was "extraordinarily important" the Government got it right.
The pair were joined by Health Secretary Andrew Lansley in addressing about 100 doctors and nurses at Frimley Park Hospital in Surrey.
Mr Cameron insisted the NHS would not go down the route of a US-style system, with people forced to "take their credit cards along to accident and emergency" before they could access treatment.
But he said that while the Government would listen and the Bill would undergo revisions, things could not stay as they were.
The number of people over the age of 85 is set to double in the next 20 years while the cost of advances in treatments and medicines is adding £600 million of extra funding pressure every year, he said.
"Taken together, these pressures threaten a squeeze on NHS resources down the line so if we want to keep a health service that is truly free at the point of use - not just this year, not just next year, but in the decades to come - we have got to make the NHS more effective."
Mr Cameron said the Government would now take time to "pause, to listen, to reflect.
"Let me be clear - this is a genuine chance to make a difference.
"Where there are good suggestions to improve the legislation, to improve the changes, those changes will be made.
"But let me be equally clear - the status quo is not an option."
Mr Cameron acknowledged there were "some big questions" from NHS workers about the way that the Government's reforms would work.
"We hear that, and we want to work with you, not against you," he said.
"The process of politics and government is about trying to improve the state of this country and institutions and take people with you at the same time.
"That does mean sometimes stopping, listening, reflecting on how we do things rather than charging ahead like we were doing previously."
Mr Clegg admitted that the Government had not got every detail right and needed to reflect on the plans.
But he said the reforms contained "common sense" ideas designed to reduce bureaucracy, put more power in the hands of communities and give more responsibility to family doctors who know patients best.
"Those ideas stay true to the vision of the NHS set out by its architect, the great Liberal William Beveridge, and they are ideas that will be preserved in our reforms," he went on.
"Does this mean we have got every detail right? Does it mean we've convinced everyone? Of course it doesn't, and that's why we are taking the time now to pause, listen, reflect and improve on our proposals.
"In process terms it's unusual - but then again, so is a Government that actually listens. I care more about getting this right than just getting it done."
Mr Lansley said he believed some people had misunderstood the Bill, but its principles had received widespread support from NHS professionals.
He insisted that the private sector - which will have an expanded role under the plans - would not be given an unfair advantage in delivering NHS services.
A new NHS Future Forum chaired by Professor Steve Field, former head of the Royal College of GPs, will look into four aspects of the Bill.
These include the role of choice and competition for improving quality, how to ensure public accountability and patient involvement, how education and training will be incorporated, and how more health professionals can be brought on board.
One of the major fears in this week's Commons Health Committee report was that GPs would have too much power and no duty to consult other professionals, such as hospital specialists.
But Mr Clegg, who has been coming under pressure from his own party, stressed today that amendments would mean other health workers had a bigger role.
Other amendments have already been promised to stop private health companies "cherry-picking" easier cases for maximum profit, while competition on price will not be allowed.
The April 2013 deadline for GPs to take on most of the NHS budget is also to be relaxed.
Shadow health secretary John Healey accused the Government of conducting a PR exercise.
"David Cameron has said nothing today to clear up the confusion or deal with the crisis of confidence in his handling of the NHS," he said.
"If the Prime Minister is serious about listening rather than PR spin, people will expect root and branch changes to his NHS plans.
"But while they claim to be listening, the Tory-led Government is in fact still ploughing on with their NHS reorganisation."
Dr Peter Carter, chief executive of the Royal College of Nursing (RCN) said he hoped the "pause will be used to reflect in detail on some of the problems nurses and other health professionals have raised" about the largest reorganisation in the history of the NHS.
"However, the RCN and other organisations have been raising these concerns for almost a year now, and need to know that they are being heard as well as listened to."
The King's Fund's chief executive, Chris Ham, said: "We welcome the listening exercise announced today but it must result in significant changes to the current proposals if the reforms are to succeed."Reuse content