Germany’s Christian Democrats on Thursday sought to deflect accusations of xenophobia in a move by the party of chancellor Angela Merkel to expand its electoral base ahead of a regional election next month.

Seventeen high-ranking CDU politicians indirectly criticised Roland Koch, the state premier of Hesse, for making juvenile crime among migrants the main issue of a re-election campaign that sparked a national outcry and saw support for the party plummet in a regional poll last weekend.