The British Medical Association (BMA) has passed a vote of no confidence in health secretary Jeremy Hunt, at its annual conference.
Representatives at the conference in Edinburgh had passed the motion with an "overwhelming majority."
Dr Jacky Davis, who put forward the motion, warned the health secretary was leading the government's "ideological attack."
Meanwhile, in his first speech as chair of the BMA's UK Council, Dr Mark Porter told delegates that medicine is becoming a profession "on the edge" as doctors try desperately to deal with the "sheer, unparalleled scale of demand".
He said: "As doctors we have one of the most privileged jobs in the world - helping patients and improving the health of the nation.
"It's what we do and it is often wonderful, inspiring and life affirming but it's easy to forget that as the NHS struggles to cope with the double whammy of cuts and structural change. I feel as if we're becoming a profession on the edge. And a medical profession on the edge, means an NHS on the edge.
"Doctors are desperately trying to just deal with the sheer, unparalleled scale of demand on existing services. And we experience overwhelming frustration that we cannot achieve the changes and improvements that we can see are so necessary to deal with this pressure.
"We need to make sure the voice of the profession is heard, if it isn't the NHS will fail."
In the 12 weeks since the Health and Social Care Act in England was introduced, Dr Porter said the government's response to the problems facing the NHS has been "inadequate and divisive", and cost improvement programmes had been "cutting resources to and beyond the bone".
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