Image caption Despite major changes to the health bill, critics are still unhappy

Lib Dem activists have failed in a bid to force a vote on controversial NHS changes at their autumn conference.

Former MP Evan Harris had led calls for delegates to be allowed to vote on legislation going through Parliament overhauling how care is commissioned and the health service is regulated.

Delegates backed his call but not by the two-thirds majority needed.

Critics say the NHS plans, already heavily modified, amount to partial privatisation and should be dropped.

The government revised its plan to restructure the NHS in England - which will see primary care trusts abolished and responsibility for commissioning care transferred to GP-led consortia - following a "listening exercise" earlier this year.

The Lib Dem leadership, which pushed for far-reaching changes to the original proposals amid concerns about levels of competition, indicated they were satisfied with the modified package.

But medical professionals are still opposed to parts of the bill, which they say they will give the private sector too much power and dilute accountability, and some Lib Dem MPs are still unhappy.

Dr Harris wanted to push the plans to a vote of Lib Dem delegates at their annual five-day conference in Birmingham, arguing that they were not included in the coalition agreement endorsed by party members after the 2010 general election.

Activists said a vote would also make the party's views clear as the plans are debated in Parliament.

'Own goal'

However, they failed in a challenge to conference rules, which would have ensured a vote on the issue.

Activists voted by 235 votes to 183 in favour of allowing an emergency motion on the shake-up to be debated on the conference floor but it did not pass the threshold for consideration.

Deputy leader Simon Hughes had warned against such a move, saying a new "shopping list" of demands on the NHS would be equivalent to "micro-managing" government policy.

"Don't score an own goal by unstitching a balanced conference," he said.

Delegates will still get an opportunity to discuss the revised NHS plans in a debate on Wednesday but the possibility of a rebellion over the issue has been averted.

Coalition ministers and critics of the proposals, such as Dr Harris and Baroness Williams, will also take part in a question and answer session on the plans on Tuesday.

Health Secretary Andrew Lansley has said claims that the NHS is set to be privatised is "ludicrous scaremongering" and the plans will give more power and choice to patients and cut bureaucracy.