Vince Cable has accused rival parties of being "fundamentally dishonest" over the deep public sector spending cuts needed to avert a Greek-style economic collapse in the UK.
Speaking during a campaign visit to the Westcountry the Liberal Democrat Treasury spokesman conceded the public was yet to fully understand how painful life will be as the next government attempts to pay off the record national debt.
Vince renewed the Lib Dem's pledge to save £15bn through measures including scrapping ineffective training programmes, cutting the child tax credit for wealthy families and stopping the winter fuel payment for young pensioners.
On cuts to public spending which accounts for around half of the South West economy, Vince said, "Things are going to be very difficult indeed. We've had the mother of all financial crises followed by a recession and many of the costs of those things have been absorbed by the government in the form of an enormous deficit.
"That is not sustainable, and if governments try to ignore it we are going to be in the unfortunate position of those countries in southern Europe, like Greece. We have got no option and the way in which politicians should address it is being specific about some of the cuts that have got to happen.
"I don't think people realise how painful it is going to be. Part of the reason is that despite our efforts the Tories and the Labour party are trying to deal with this problem by saying its all going to be solved by making the public more efficient.
"Efficiency is just a way of saying we are going to cut services indiscriminately…"