Updated

A top official in Chancellor Angela Merkel's party says he's not surprised by the departure of a hard-line conservative lawmaker who had increasingly been at odds with the German leader, but regrets the manner of it.

Lawmaker Erika Steinbach announced she was leaving Merkel's Christian Democratic Union in a newspaper interview. She argued that Merkel's government has exceeded its mandate by allowing large numbers of migrants in and eurozone bailouts to Greece and by accelerating Germany's exit from nuclear power.

CDU general secretary Peter Tauber told the dpa news agency Sunday that Steinbach's departure was no surprise.

But he added: "I find it regrettable that Mrs. Steinbach is going about it this way. Spreading excessive and unjustified accusations via the media and not in a direct conversation is not conservative."