Updated

German Chancellor Angela Merkel says her conservative bloc is embarking on exploratory talks with the Social Democrats with the goal of forming a so-called "grand coalition," despite the center-left party saying it would also consider other options.

Merkel told reporters Monday after meeting with her party's leadership that anything other than a grand coalition would be considered a failure of the preliminary talks.

Merkel's conservatives and the Social Democrats have governed Germany together since 2013 in a grand coalition. The Social Democrats ruled out another after performing poorly in September's election, but reluctantly reconsidered after Merkel's talks with two smaller parties collapsed.

Still, party leader Martin Schulz has left options open, saying exploratory talks will also consider the possibility of a looser arrangement, like possibly supporting a Merkel-led minority government.