It is reported that health spending could rise by up to £18 billion over the next three years when the chancellor announces his Budget next week.

Annual NHS spending increases could total seven per cent compared with the 6.4 per cent under the current review.

This will be funded by tax increases of more than £5 billion per year and higher national insurance contributions.

Plans are also being considered for NHS spending over the next 20 years.

At Treasury questions yesterday, Brown attacked the Tories following a leaked speech by shadow health secretary Dr Liam Fox in which he said the NHS "does not work and can't work".

In his Sedgefield constituency yesterday, the prime minister asked: "Do we build up our NHS through investment and reform? Or do we run it down, charge people for care, force people to go private, as the Conservatives want?"

Speaking to doctors yesterday, Dr Fox denied that there was anything wrong in considering other funding methods besides taxation.

"We've got a problem where the NHS and health care has been synonymous. We're here to break that," he said. "And that means we raise money from people through tax, by certainly health insurance...and even more so if it means from self-pay."

The Mirror today reports that a private insurance company, offering health insurance, has made a donation to Fox which does not appear in the register of members interests.