diff --git a/cython/plist.pyx b/cython/plist.pyx
index 3c6389c..d4f8d68 100644
--- a/cython/plist.pyx
+++ b/cython/plist.pyx
@@ -863,6 +863,8 @@
     is_binary = fp.read(6) == 'bplist'
     fp.seek(0)
 
+    cdef object cb = None
+
     if not fmt:
         if is_binary:
             if 'b' not in fp.mode:
@@ -888,6 +890,8 @@
 cpdef object loads(data, fmt=None, use_builtin_types=True, dict_type=dict):
     is_binary = data[0:6] == 'bplist'
 
+    cdef object cb = None
+
     if fmt is not None:
         if fmt not in (FMT_XML, FMT_BINARY):
             raise ValueError('Format must be constant FMT_XML or FMT_BINARY')