Provisional recommendations by the Competition Commission are ‘clearly wrong' private hospital groups have said, adding that they will take steps to contest the recommendations if they appear in the final report.
Commenting, Stephen Collier, CEO of BMI Healthcare, told it was to sell hospitals in London, said it was "bizarre" for the Competition Commission to claim it was making excess profits and should sell seven hospitals.
He added: "However at its core the Commission has still simply not grasped how the market for private healthcare works. Its flawed analyses have been used to support its provisional divestment remedy which we regard as unjustified.
"BMI Healthcare and its hospitals do not exercise market power or make excess profits at the expense of patients; the Commission still fails to make any case to the contrary, fatally undermining its case for divestments.
"Its reduction in the number of proposed divestments is a tacit recognition that its own analysis, which we have had to drag out of the Commission via the courts, simply does not stand up.
"If the Commission's final remedies are unfairly detrimental to BMI Healthcare, we will take whatever steps are appropriate to ensure that they do not undermine our organisation and its continued ability to deliver high quality healthcare to those who matter - our patients."
HCA added it also contests Competition Commission (CC) plans to force sale of London Bridge Hospital and The Princess Grace Hospital, two of its hospitals.
Mike Neeb, CEO and President of HCA International, said: "The Competition Commission's provisional recommendations are plainly wrong.
"The CC's own report acknowledges there are nearly 50 competitors in Greater London, our ownership of these hospitals encourages competition and drives a higher standard of care among hospitals in the UK.
"The CC has misunderstood the market and is threatening unjustified and unfair remedies. To forcibly divest hospitals from successful healthcare organisations cannot be good for either patients or our economy.
"We are the only private health provider in the UK to publish independently assessed clinical results across cancer care, cardiac surgery, neurosurgery and intensive care."
Spire Healthcare, in contrast, was more welcoming in its response, claiming the summary supports its view that Spire Healthcare is not anti-competitive.
However, four remedies will affect Spire - relating to consultant incentive schemes, the management of PPU operations by private operators, the collection and publication of information on private hospitals and consultants' performance, and the provision by consultants of fee information to patients.
Spire said it "has no issue with them and will work with the CC to make them as effective as possible".
Rob Roger, Chief Executive of Spire Healthcare, said: "We welcome the publication of the Competition Commission's provisional remedies, which supports our view that Spire Healthcare is not anti-competitive and are pleased that none of the divestment remedies relate to Spire."