European Union Commission President Jean-Claude Juncker | Thierry Charlier/AFP via Getty Images Juncker: ‘Some established German politicians make AfD acceptable’ Juncker also warned of end of Schengen if Germany closes borders.

European Commission President Jean-Claude Juncker accused German politicians in established parties of encouraging the far-right Alternative for Germany party, in an interview published Wednesday evening.

Juncker told German newspaper Handelsblatt he did not want to name anyone in particular, but “there are politicians in German parties, who use the same vocabulary and cultivate the same xenophobic resentment as the [Alternative for Germany] AfD.”

Such politicians should not be surprised if people then prefer to vote for the original, namely, the AfD, he said.

On the AfD's success in past regional elections, Juncker said that “in an established democracy like in Germany there are temporary deviations from the normality." For him, the AfD success was "a slip" and a sign of difficult times.

Ahead of the European summit on migration, Juncker also warned that if Germany closes its borders, a domino effect will take place. “Then, Schengen will slowly but surely be carried to the grave.” In the end, that will make the European single market as well as the euro senseless, he added.