MUNICH (Reuters) - Chancellor Angela Merkel’s Christian Democrats (CDU), embroiled in a leadership crisis, must unite and keep their ruling coalition stable as Germany takes on the rotating European Union presidency this year, Greens leader Annalena Baerbock said.

FILE PHOTO: Annegret Kramp-Karrenbauer, outgoing leader of Germany's Christian Democratic Union (CDU), attends a Reuters interview in Berlin, Germany, February 12, 2020. REUTERS/Hannibal Hanschke

CDU leader Annegret Kramp-Karrenbauer plunged the party into crisis on Monday when she gave up her ambitions of succeeding Merkel - a move that raised questions over the future of the conservatives’ coalition with the Social Democrats (SPD).

The center-left SPD has signaled it could quit the coalition if Merkel is forced out as chancellor - a scenario that Baerbock said could not be allowed to unfold during Germany’s EU presidency, starting on July 1.

“We cannot have a situation in the middle of the EU presidency - when we have big, big questions in Europe - for there to suddenly be a vote of confidence raised in Germany,” Baerbock told Reuters at the Munich Security Conference.

Her comments suggest the opposition Greens, which are strong contenders to take a role in Germany’s next government, are not looking to take advantage of the CDU turmoil any time soon.

Germany’s next federal election is due by October 2021.

The CDU is starting a selection process - that could take months - to decide who will lead the party and run as chancellor in that election. The same person will probably, but not necessarily, hold both posts.

The possibility of having a rival as party leader while she remains chancellor may be unworkable and force Merkel, who will not seek re-election after leading Europe’s biggest economy for around 15 years, to stand down early.

This could trigger an early election, not least because the SPD have made clear their coalition deal is only with Merkel.

But Baerbock urged the CDU to show stability.

“Germany needs a stable government in the year of the EU Council presidency,” she said on Saturday. “Otherwise we don’t need to talk about a common European foreign and security policy at all.”

A survey by pollster Forsa on Saturday put support for the Greens at about 24%, second only to the CDU’s conservative alliance with its Bavarian sister party, the Christian Social Union (CSU), on 27%.