Health and social care bill to be delayed by six months as Nick Clegg says it would be wrong to 'bounce' it through parliament

The government's troubled NHS reforms will be delayed by at least six months after Nick Clegg announced that the health and social care bill is to be sent back to MPs for detailed examination.

In a speech to patients and medical health professionals at University College London hospital, Clegg said it would be wrong to "bounce" the bill through parliament.

The deputy prime minister, who buried Andrew Lansley's 2013 target for the changes by rejecting "arbitrary deadlines", said a revised version of the bill would be sent back to MPs to examine at committee stage. Aides suggested Clegg's announcement would delay the bill by a few months because it had already completed that stage.

In his most dramatic intervention in the government's NHS "listening exercise", Clegg also announced:

• The controversial health regulator Monitor will not "push competition". Its main duty will be to protect the needs of patients.

• The membership of the GP-led consortiums, which lie at the heart of the reforms, will be opened up and no doctors will be forced to join. Lansley had hoped to hand around 65% of the NHS budget to the new consortiums, which are designed to hand commissioning powers to GPs.

• The NHS will continue to have a mix of providers but there will not be a "competition-driven dog-eat-dog market" in which the NHS is "flogged off to the highest bidder". Clegg said there would be no privatisation of the NHS.

• There will be "no sudden, top-down opening up of all NHS services to any qualified provider".

• Health and social care budgets will be brought closer together.

Clegg made clear that in light of the "substantive" changes it was important to give MPs a chance to re-examine the bill in committee after the government's "listening exercise" ends next month. The health and social care bill has already passed that stage and was due to complete its final stages in the Commons before the summer recess ahead of being sent to the Lords.

The deputy prime minister said: "I don't think it would be right for us to hold this listening exercise – to make big changes to the legislation – and then to seek to bounce it through parliament. It is very important that MPs, who represent millions of patients up and down the country, have the opportunity to really look at the details that we are proposing.

"I think we will need to send the bill back to committee. I have always said that it is best to take our time to get it right rather than move too fast and risk getting the details wrong.

"We will introduce substantive, big changes. My desire – I think everyone's desire – is just to get it right. The NHS is simply too precious, too important to millions of people in this country to rush things and get it wrong."

John Healey, the shadow health secretary, said: "I welcome Nick Clegg backing Labour's motion to send the health bill back to the House of Commons to rerun its committee stage. The government's plans for the NHS need to be radically rethought. If fundamental changes are going to be made to the legislation they need full and proper scrutiny in parliament."

Clegg highlighted the scale of the changes when he took apart some of Lansley's original ideas. "As Andrew Lansley confirmed earlier this week, the duty of Monitor, the health regulator, will not be to push competition – especially not at the expense of integrated services and collaborative practices like clinical networks. Monitor's main duty will be to protect and promote the needs of patients instead, using collaboration and competition as a means to that end."

Clegg made clear that Lansley's 2013 deadline has been shelved. "Change won't happen overnight and arbitrary deadlines are no good to anyone."

Clegg said GPs should not be forced to join the new consortiums. "Family doctors should be more involved in the way the NHS works. But they should only take on that responsibility when they are ready and willing, working with other medical professionals, too.

"We aren't going to just sweep away tiers of NHS management. NHS managers will carry on doing the commissioning in areas that aren't yet ready. And there'll be no sudden, top-down opening up of all NHS services to any qualified provider."

Dr Evan Harris, the former Liberal Democrat MP who has led the charge against the NHS reforms, welcomed Clegg's announcement. Harris proposed a successful motion against the NHS reforms at the party's spring conference in March.

"Everything that Nick Clegg said today, and indeed in previous public statements, about the changes to the health bill that he is promising is consistent with what the party's conference voted to demand," Harris said.

"The party rank and file will be pleased about that and will expect that in later announcements the other changes called for are also to be delivered." Those areas included a bar on the outsourcing of commissioning, protection against the undermining of existing services by contracting out, and strong, "democratic" oversight of commissioning groups.