Germany's Merkel hopes SPD will approve talks with her CDU party

German Chancellor Angela Merkel speaks during a joint news conference with Bulgaria's Prime Minister Boyko Borissov in Sofia, Bulgaria, January 20, 2018. REUTERS/Stoyan Nenov

SOFIA (Reuters) - German Chancellor Angela Merkel said on Saturday she was optimistic that the centre-left Social Democrats (SPD) would approve the start of formal coalition talks with her conservative CDU party at a special congress on Sunday.

"We will wait for the SPD party congress and then hopefully start coalition talks," Merkel said during a news conference in Sofia.

Merkel added she was convinced that European leaders would strengthen the euro zone, for example by agreeing on further measures to complete a banking union.

(Reporting by Angel Krasimirov and Andreas Rinke; Writing by Michael Nienaber; Editing by Alexander Smith)