A £3bn scheme to expand the "privatisation" of the NHS will go ahead despite its almost certain rejection by Labour's conference, the government vowed last night.

Health Secretary Patricia Hewitt pledged to press ahead with plans for a second wave of privately-run treatment centres, capable of treating 300,000 patients a year.

Last night, delegates in Brighton were believed to have backed a trade union resolution demanding a suspension of the expansion of the private sector into the NHS, pending a review.

A card vote was held on the crucial motion - delaying a result until early today, although the unions were expected to carry the day.

But the Government is not bound by the decision, allowing ministers to press ahead with a policy condemned by its critics as "privatisation".

Unison, the public service union, has claimed the changes risk undermining service quality and increasing "inequality of access" to care.

General secretary Dave Prentis won applause when he angrily demanded: "An NHS driven not by patient need but by profits and markets - is that really our vision?"

Mr Prentis said it was unacceptable to have different parts of the NHS competing for patients and accused ministers of not learning from flawed Tory policies of the past.

But Ms Hewitt has denied claims that the changes amount to privatisation, insisting it is wrong to claim that NHS buildings and staff will be transferred to private providers.

She described the use of the private sector to operate on patients as a success story that was providing quicker treatment for people facing unacceptably long waits.

Yesterday, Ms Hewitt told the conference: "We are not selling hospitals or any other NHS facilities to the private sector."

Rank-and-file anger over the use of the private sector this week sparked the launch of a Keep Our NHS Public campaign, led by former health secretary Frank Dobson.

Speaking in the debate, Blaydon MP David Anderson protested that NHS staff were having to worry about structural change, rather than how to improve care.

And he warned that the Government was repeating the mistakes made over the creation of foundation hospitals by not consulting properly with staff on the ground.

Mr Anderson said: "We can't renew New Labour, or even pretend to be change-makers, if we don't engage with the people who have to deliver our promises."

A defeat for Mr Blair would be the second of the week, following a vote to re-legalise secondary strikes, in the wake of the Gate Gourmet dispute - another vote he has pledged to ignore.