The Conservative party leader, William Hague, in a bid to turn next month's general election into a referendum on the pound, warned voters this afternoon that they had just 12 days to save their currency.
But Prime Minister Tony Blair ignored Hague's challenge and instead gave a passionate speech on the country's state-funded health service, saying it would be a disaster for British health care if the Tories were elected.
Margaret Thatcher also re-entered the fray, declaring she would never favour giving up the pound.
Blair mocked Thatcher's intervention and her creed of individualism, while not addressing her words on the currency.
"You remember what she said. 'There is no such thing as society.' For me that has always been a defining moment in politics," Blair told supporters in Preston, northwest England.
"Because there is such a thing as society. The National Health Service represents it," he said.
With Labour in the polls by up to 20 points, William Hague signalled that the fate of the pound was now his party's main hope of turning round its fortunes. Polls show some 70 per cent of Britons want to stay out of the euro club.