Ministers will attempt to fight off further controversy over the government’s troubled NHS reforms as the Health and Social Care Bill resumes its passage through the House of Lords today.

Liberal Democrat peers are seeking to rewrite key elements of Andrew Lansley’s plans through a series of detailed amendments to be debated in the upper chamber this week.

The changes, which are said to have the tacit backing of the Lib Dem leadership, including measures to strip out proposals to increase competition in the NHS.

At the same time, the Royal College of Physicians - representing hospital doctors - is meeting today in emergency session to discuss whether to formally ballot the views of its 26,000 members on the legislation.

An online poll conducted by doctors opposed to the reforms found 92.5 per cent of RCP members believed they should now be abandoned, according to the Observer, which was given access to the findings.

A spokeswoman for the college said: “The RCP continues to have serious concerns about the reforms and has been lobbying vigorously for changes to the Bill since its publication.”

If the RCP were to come out against the legislation, it would bring it into line with the other royal colleges in calling for the bill to be withdrawn, leaving ministers looking even more isolated.

In a further blow, former NHS chief executive Lord Crisp yesterday denounced the reform plans as “a mess”, saying they were “unnecessary, confused and confusing”.

David Cameron has made clear that he intends to see the legislation through, warning last week of “chaos” in the NHS if the reform proposals were abandoned now.

Chancellor George Osborne said at the weekend that it was essential the changes went through with the NHS was to be affordable in future while meeting the needs of an ageing population.

But with Lib Dem activists threatening a revolt at the party’s spring conference next month, Labour sought to keep up the pressure - urging Lib Dem peers to vote with them to kill off the bill altogether.

While that looks unlikely, Labour leader Ed Miliband said that it was still not too late for David Cameron to think again and abandon the legislation.

“Throwing all the pieces of our NHS up in the air and seeing where they land is not the right way to go about reform,” he wrote in an article in the Times.

“Only political pride is preventing this prime minister from dropping his bill. If he ploughs on, he will not only destroy trust in himself, he will also prevent the real change that the NHS needs.”