German Chancellor and leader of the Christian Democratic Union (CDU) Angela Merkel makes a closing statement during the second day of the CDU party congress in Karlsruhe, Germany December 15, 2015. REUTERS/Kai Pfaffenbach

BERLIN (Reuters) - Germany wants to reach a deal to keep Britain in the European Union but cannot compromise the 28-member bloc’s core principles, Chancellor Angela Merkel said on Wednesday ahead of an EU summit.

“On the one hand, we want to reach an agreement with which the British government can successfully campaign, in the forthcoming referendum, to remain in the European Union,” she told the Bundestag lower house of parliament.

“On the other hand, we don’t want to, and we won’t, call into question the core principles of European integration. These include in particular the principle of free movement and the principle of non-discrimination between European citizens.”