The spread of populist movements is threatening European integration and efforts to find joint responses to immigration, security and other shared concerns, ECB President Mario Draghi said in an interview published on Wednesday.
In some of his strongest recent comments on political developments, Draghi told Spain's El Pais newspaper that EU citizens' main worries were "now immigration, counter-terrorist security measures, defence and border protection".
"All of these are supranational affairs that require a common response. European integration is the appropriate response, but this has become weaker in recent times, partly because of populist movements," he added.
Draghi did not name particular parties. But a string of movements has shaken up the political landscape, including Britain's UKIP, which helped drive the Brexit debate, and France's National Front, which wants its own anti-EU referendum.
With elections coming up in France, Germany and the Netherlands, three countries with rising populist movements, the risk has increased that ruling parties shift focus away from needed structural reforms, keeping a heavy burden on the ECB to prop up growth.
His comments holding up integration as an answer to security concerns came as the European Commission was due to present its biggest plan in more than a decade to revitalise the 96-billion-euro defence industry with a new joint research fund.