The east German spelling suggested that West Berlin was not really part of `` Berlin '' as a whole , but a separate place . East Berlin was officially called Berlin , Hauptstadt der DDR ( `` Berlin , Capital of the GDR '' ) , or simply `` Berlin , '' by East Germany .
Starting from 31 May 1961 , East Berlin was officially called Berlin , Capital of the GDR ( , replacing the formerly used term Democratic Berlin ) , or simply `` Berlin , '' by East Germany , and `` Berlin ( Ost ) '' by the West German Federal government .