The Royal College of Nursing’s chief executive has said the government’s Health Bill can still be defeated, even though the prime minister has reiterated his support for the reforms.

The RCN and the Royal College of Midwives, along with the other groups most strongly opposed to the bill, were excluded from a health summit held by David Cameron on Monday.

Mr Cameron said at the meeting the bill would be passed despite opposition. It has yet to pass its report stage in the Lords and, afterwards, has to be voted on by MPs in the Commons.

Speaking after the Downing Street event, RCN chief executive and general secretary Peter Carter told HSJ that Conservative and Liberal Democrat MPs were increasingly worried about it.

His comments come as the BBC reports senior Liberal Democrats in the government are also concerned about the unpopular reforms.

Mr Carter said feeling among MPs could increase because further medical royal colleges - including the influential Royal College of Physicians - could decide they are completely against the bill in coming weeks. He said it meant pressure on the government to abandon it was still growing, and opponents’ calls for it to be dropped could still succeed.

The Royal College of Paediatrics and Child Health today joined those colleges calling for the bill to be withdrawn. The decision was taken by the RCPCH’s council following a survey of UK members which saw 79 per cent of respondents vote for the college to call for the “outright withdrawal” of the bill rather than continue to push for amendments.

Mr Carter said numerous backbench coalition MPs had told the RCN privately they were “confused” about the reason for the reforms, particularly as the NHS was not a major election issue.

He said: “Politicians from right across the spectrum speak with us… A lot of people are thinking, ‘Should we have gone down this route - was it worth it?’

“There is pointed concern even from party stalwarts about whether they have got it wrong.

“Most are keeping their own council but privately more than a dozen have said to us, ‘Yes, this is perplexing.’”

Responding to his exclusion from the Downing Street summit, Mr Carter said he believed the RCN would be involved in future discussions. He said: “This is short term in the sense they are disappointed with us and we are disappointed with them.

“But I’ve got no doubt that in order to move forward all of the organisations that were not invited have to be engaged. It is just not a sensible way forward [to exclude groups].”

The British Medical Association and Royal College of GPs were also excluded from the Monday meeting.

In a statement the BMA accused the government of “selective listening”. However, a senior BMA source told HSJ that if the bill was passed the organisation would have to soften its stance on the reforms. The source said: “At some point we have to knuckle down and make things work.”

RCGP chair Clare Gerada made clear the college would continue to fight the bill. However, she told HSJ if it was passed the college would “still support our members in getting engaged [with commissioning]”. She said the tone of debate about reforms should change and said: “It has become far too polarised at the moment.”