diff --git a/mercurial/ui.py b/mercurial/ui.py
index db0646afb7258ed5beca38129ba12bb2dda838a7_bWVyY3VyaWFsL3VpLnB5..31c9e2a702d128c5d0e2aa35eaa8cf5434029910_bWVyY3VyaWFsL3VpLnB5 100644
--- a/mercurial/ui.py
+++ b/mercurial/ui.py
@@ -653,5 +653,5 @@
         printed.'''
         if self.tracebackflag:
             if exc:
-                traceback.print_exception(exc[0], exc[1], exc[2])
+                traceback.print_exception(exc[0], exc[1], exc[2], file=self.ferr)
             else:
@@ -657,5 +657,5 @@
             else:
-                traceback.print_exc()
+                traceback.print_exc(file=self.ferr)
         return self.tracebackflag
 
     def geteditor(self):