diff --git a/diskimage_builder/elements/pip-and-virtualenv/install.d/pip-and-virtualenv-source-install/04-install-pip b/diskimage_builder/elements/pip-and-virtualenv/install.d/pip-and-virtualenv-source-install/04-install-pip
index 78acc187d..229ec6219 100755
--- a/diskimage_builder/elements/pip-and-virtualenv/install.d/pip-and-virtualenv-source-install/04-install-pip
+++ b/diskimage_builder/elements/pip-and-virtualenv/install.d/pip-and-virtualenv-source-install/04-install-pip
@@ -265,7 +265,7 @@ else
         # time and you had to use "python -m venv".  Since then virtualenv
         # has gained 3.4 support so the pip install below will work
         if [[ ${DIB_PYTHON_VERSION} == 3 ]]; then
-            packages+="python3-pip python3-virtualenv"
+            packages+=" python3-pip python3-virtualenv"
         fi
 
         apt-get -y install $packages