Sefton Central Labour MP Bill Esterson said proposals to introduce charges to go to A&E would mark the end of the NHS.
Calls to introduce a fee to attend accident and emergency and even for GP appointments came after Health Secretary Jeremy Hunt announced plans to make changes to NHS contracts.
Bill Esterson warned that this could be another leap by the Tories to privatise the National Health Service.
Bill said: "Proposals to charge people £10 or £20 to go to A&E are outrageous, but are just another example of how this government could privatise the NHS. It is copying the American system where the only people who can get access to health care are those who can afford it.
"The suggestion is horrific. We could end up seeing people being rushed to A&E having suffered an injury, only for those people to be turned away unless they can pay to be seen. That's not what the NHS was set up for.
"It is morally repugnant, but my fear is that this right-wing government might leap at this chance to privatise another element of the NHS under the pretence of getting to grips with the A&E crisis. But they won't tell you it is an A&E crisis of their making, caused by cuts in the numbers of staff in health and in social services.
"There is no doubt that the many Tories and Lib Dems with stakes in private health care companies want to see the demise of the NHS, but it is something that I and many thousands of people in Sefton Central will fight against."
Former Tory Cabinet Minister Liam Fox has even called for an end to ring-fenced funding for the NHS.
Bill said: "It is clear to us all now just how right-wing this government is. From the privatisation of the NHS to the attacks on the poorest.
"Former Tory Minister Liam Fox, who is still very influential amongst his Tory colleagues, is now calling for cuts to the NHS.
"They are trying their best to run down the NHS at a time when the dedicated staff are working so hard to save it.
"How the Liberal Democrats can continue to prop up this right-wing government is beyond me. How can the Lib Dems support the privatisation of the NHS in which you could soon only get treatment if you can pay?
"The core principle of the NHS was free at the point of use. That is a principle worth fighting for and one which I will battle to save."