Ring-fenced funding for the National Health Service must end after the next general election, a senior Conservative has said.
Britain is lagging behind other countries in key areas such as cancer outcomes and the idea that ploughing money into the NHS improves standards had been "tested to destruction", according to Liam Fox.
The former defence secretary backed Prime Minister David Cameron's decision to keep his promise to increase funding in real terms, but urged him not to include such a pledge in the next Conservative manifesto.
Dr Fox told The Times: "I think we've tested to destruction the idea that simply throwing lots more money at the health service will make it better.
"The increase over the last decade has been phenomenal and yet a lot of our health indicators lag behind other countries, particular things like stroke outcome or a lot of cancer outcomes.
"We've become obsessed with throughput and not outcomes and that has been hugely to the detriment of the patients in our system.
"If you treat the National Health Service itself as being the important entity, and not the patients, then you're on a hiding to nothing."
Protected budgets have proved unpopular with many Tory backbenchers who have been angered that a small number of budgets, including overseas aid, have been ring-fenced while the rest of government has been hit by swingeing cuts.
In the interview with The Times, the former GP called for aid to be pulled from states that do not share Britain's values and said the Tories would need to outline "totemic" tax cuts in the run up to the 2015 poll.
Dr Fox added: " Ring-fencing anything, any budget within a diminishing total leads to bigger and bigger distortions.
"They become, by definition, bigger and bigger proportions of the spending total... It also has a restricting ability inside government to move money around when there is a particular problem.
"Anybody who has worked with or around the NHS knows there is still a huge amount of waste associated with it."