BERLIN (Reuters) - German President Frank-Walter Steinmeier will host a joint meeting next week between Chancellor Angela Merkel, the leader of the center-left Social Democrats (SPD) and the head of the Bavarian Christian Social Union (CSU), a spokeswoman said. Merkel s Christian Democrats (CDU) and their CSU Bavarian sister party have ruled with the SPD in a  grand coalition  since 2013 and their caretaker government remains in place after an election in September.  After meeting this week with the leaders of the CDU, CSU and SPD the federal president has agreed to meet a joint meeting at Schloss Bellevue,  Steinmeier s spokeswoman said in a statement.  The meeting takes place next week. The exact date will be communicated at a later time.     
German president to hold joint talks with Merkel, Schulz next week