David Cameron has warned the UK's annual interest payments could surge to £70bn if cuts are not made urgently as he told the nation to prepare for "unavoidably tough" measures.
In a speech at the Open University in Milton Keynes, the Prime Minister said interest payments on the country's "staggering" debt will rise to £70bn a year in five years if cuts are not immediately put in place.
The UK currently pays £42bn a year in interest on the deficit.
"This is the sober reality that we have to set out for the country today," he said. "Unless we act now, interest payments in five years time could end up being higher than the sums we spend on our schools, on climate change and on transport charges combined."
He said the legacy left by the last Government, including a shrunken private sector, is "terrible" and warned of hard times ahead.
"The measures that we need to deal with the legacy will be unavoidably tough."
But he said such cuts are necessary for the long-term good.
"We will carry out Britain's unavoidable deficit reduction plan in a way which strengthens and unites our country."
Underlining the global nature of the financial fallout, he added: "We are not alone in this - many countries around the world have been living beyond their means and they, too, have to face the music."
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