Wolfgang Schauble, Germany's departing finance minister, has warned of "bubbles" in the economy.
He said he was concerned, along with economists about "the increased risks arising from the accumulation of more and more liquidity and the growth of public and private debt" and warned of the dangers of "new bubbles forming" as a result of central bank policies.
In an interview with the Financial Times he said the risks across the Eurozone are still "too high" and need to be reduced.
"Think of the bank balance sheets in many EU member states. We have to ensure that we will be resilient enough if we ever face a new economic crisis - we won't always have such positive economic times as we have now... And we will have to work on this all the time," he said.
He also warned of "demagogues" who say Europe costs too much. "The British have shown us how foolish that is," he said.
"In that respect they made a great contribution to European integration, though in the short term that doesn't really help Britain," he added.
After eight years as one of the most influential people in the Eurozone economy, Schauble will become the head of the lower house of Germany's parliament, also leaving the Eurogroup, the EU's group of leading finance ministers.