Opposition parties were deeply sceptical about Mr Blairs promise, suspecting it was a sleight-of-hand to deflect mounting criticism of the governments handling of the NHS.

The Conservatives spent a day working out how to respond to the announcement, while arguing it was a nice headline grabber that doesn't add up to a row of beans without explaining where the money is coming from .

On Tuesday, Conservative leader William Hague launched a stronger attack, saying the government would have to abandon its political ideology and embrace the independent health sector if it wanted to meet its target.

It is time to stop treating health as a political football and to seek cross-party agreement on the best way forward, said Mr Hague.

Liberal Democrat health spokesman Nick Harvey said the extra£2bn a year for five years promised by Mr Blair would not get the UK close to the European average of spending 8.6 per cent of GDP on health. He said at least£4bn a year would be needed.

Chancellor Gordon Browns much-mooted£8bn-10bn surplus would mean little difficulty funding the promise in the short term, Mr Harvey added. But over the long term extra taxation must come into it.