One of the German government's closest economic advisers has warned the euro has a "limited chance of survival" and may only last for another five years.
In an interview with newspaper Welt am Sonntag, Dr Konrad, chairman of a scientific council that advises the finance ministry, said: "Europe is important to me. Not the euro. And I would only give the euro a limited chance of survival."
Asked whether the single currency could last five years, he said: "A concrete period is hard to identify as it depends on so many factors. But five years sounds realistic."
He warned no country can pile up debts without risking their investors will pull out, the Telegraph reports.
"It is in each [country's] interests to keep their own debts as small as possible.
"Where the limit lies has to be individually decided. That depends among other things on economic growth and the growth of population," he said.
Konrad added that countries should have the freedom to get into debt, but they must carry "sole responsibility".
His views appear to go against the official German government view the euro must be held together to provide unity in Europe, according to the Telegraph.
In a speech to the Bundestag two years ago, German chancellor Angela Merkel told German MPs: "Nobody should take for granted another 50 years of peace and prosperity in Europe ... that's why I say: If the euro fails, Europe fails."
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