Those leaders are right to be worried. On Thursday, far-right French presidential candidate Marine Le Pen, who polls suggest will reach the final round of the election in May, called for an end to free education for foreign children living in France.
It is a sign of the times that those comments are unlikely to dent Le Pen’s popularity. So it would take a brave politician who suggests not only educating immigrant children for free but also waiving some of the debt obligations of adults living in another country.
Such is the concern of mainstream politicians about the rise of populism in Europe and beyond.
But they would be wrong not to act.
The debacle that has been the handling of Greece’s financial woes — and that of the wider eurozone debt crisis — is very much a cause of the declining esteem in which the European project is held, which in turn has assisted the rise of Le Pen and her ilk.
It may well be too late to stop the tide of anti-European Union feeling. In the UK, that has been proven at the ballot box.
But that is no reason not to try. A good start would be solving the Greece problem — the first chapter in the eurozone debt crisis.
Meaningful debt relief could bring a Greek return to the bond markets next year.
What better way to show the citizens of Europe that the EU can get things done.