diff --git a/contrib/unaccent/Makefile b/contrib/unaccent/Makefile
index 652a3e774c..3ff49ba1e9 100644
--- a/contrib/unaccent/Makefile
+++ b/contrib/unaccent/Makefile
@@ -26,7 +26,9 @@ endif
 update-unicode: $(srcdir)/unaccent.rules
 
 # Allow running this even without --with-python
-PYTHON ?= python
+ifeq ($(PYTHON),)
+PYTHON = python
+endif
 
 $(srcdir)/unaccent.rules: generate_unaccent_rules.py ../../src/common/unicode/UnicodeData.txt Latin-ASCII.xml
 	$(PYTHON) $< --unicode-data-file $(word 2,$^) --latin-ascii-file $(word 3,$^) >$@