diff --git a/README b/README
index e171ee5aa..27c3eecff 100644
--- a/README
+++ b/README
@@ -102,6 +102,9 @@ The full requirements are described below.
 +--------------+-------------+---+-----------------------------------------+
 | augeas       | 1.0.0       | R |                                         |
 +--------------+-------------+---+-----------------------------------------+
+| xz           |             | R | Used to compress disk images.           |
+|              |             |   | Used by virt-builder for compression.   |
++--------------+-------------+---+-----------------------------------------+
 | po4a         |             |R/O| Required if compiling from git.         |
 |              |             |   | Optional if compiling from tarball.     |
 |              |             |   | For localizing man pages.               |
@@ -167,8 +170,6 @@ The full requirements are described below.
 | gpg          |             | O | Used by virt-builder for digital        |
 |              |             |   | signatures                              |
 +--------------+-------------+---+-----------------------------------------+
-| xz           |             | O | Used by virt-builder for compression    |
-+--------------+-------------+---+-----------------------------------------+
 | findlib      |             | O | For the OCaml bindings.                 |
 +--------------+-------------+---+-----------------------------------------+
 | ocaml-gettext|             | O | For localizing OCaml virt-* tools.      |