diff --git a/icu4c/source/configure.ac b/icu4c/source/configure.ac
index b6065af7997..c858e1fd428 100644
--- a/icu4c/source/configure.ac
+++ b/icu4c/source/configure.ac
@@ -1349,6 +1349,7 @@ AC_CONFIG_FILES([icudefs.mk \
 		tools/pkgdata/Makefile \
 		tools/tzcode/Makefile \
 		tools/gencfu/Makefile \
+		tools/escapesrc/Makefile \
 		test/Makefile \
 		test/compat/Makefile \
 		test/testdata/Makefile \