Chancellor Angela Merkel’s preferred successor as head of Germany’s conservatives warned the Social Democrats (SPD) on Thursday that quitting the ruling coalition after a weekend regional vote would trigger a federal election. The conservatives and SPD are facing a second local election drubbing in two weeks during Sunday’s vote in the western state of Hesse, Reuters said. SPD members are piling pressure on their own leaders to abandon the ‘grand coalition’ they reluctantly joined in March and reinvent themselves. “If this government were to break apart now, it would lead to new elections,” said Annegret Kramp-Karrenbauer, the general-secretary of Christian Democrats (CDU), who Merkel promoted to the senior party post in February in a clear signal that she is the chancellor’s choice to succeed her. Merkel has been weakened by her 2015 decision to let more than a million migrants into Germany.