Labour MP's clashed with a long-term opponent of the private finance initiative at a meeting of the influential Commons Treasury select committee last week.

Professor Allyson Pollock of University College London told the committee, which is investigating PFI, that the scheme was shrinking NHS capacity and schemes fell victim to a huge escalation in costs by the time full business cases were released.

She insisted that total bed numbers were being cut by about 30 per cent under current and proposed PFI schemes in an effort to fill an affordability gap between the public and private sector.

But Liz Blackman, Labour MP for Erewash, said her comparisons between the costs of PFI and public sector schemes did not include maintenance costs in the public sector.

Professor Pollock replied: We realise that we cannot compare like with like. That isn't our fault - that is because of the lack of transparent information available.

We are actually talking about shrinking what we have got. It is painted to the public as a shift to primary care and quality care. But when we look at the evidence we are seeing this huge contraction in the acute sector. But it is still revenue-hungry and none of the money is being diverted to primary care.

Committee chair Giles Radice, Labour MP for Durham North, cited run-down acute services in the area as evidence that my constituents, who are not so sophisticated as Professor Pollock, would be more concerned to get new services than about arguments on funding mechanisms.

He was backed by Ms Blackman, who said her constituents in Derby are not too concerned about some of the issues which have been raised by Professor Pollock and more worried about some of the buildings which are a disgrace.

Professor Pollock told them: I am no defender of the record of capital spending on the NHS, which has been absolutely atrocious. But what are the medium and long-term consequences? That is what I am here to explore.