diff --git a/tox.ini b/tox.ini
index 7b20901..cb5ca00 100644
--- a/tox.ini
+++ b/tox.ini
@@ -44,6 +44,7 @@ basepython = python3
 commands = python setup.py build_sphinx
 
 [testenv:debug]
+basepython = python3
 commands = oslo_debug_helper {posargs}
 
 [testenv:releasenotes]
@@ -63,6 +64,7 @@ exclude=.venv,.git,.tox,dist,doc,*lib/python*,*egg,build,releasenotes
 
 
 [testenv:pip-check-reqs]
+basepython = python3
 # Do not install test-requirements as that will pollute the virtualenv for
 # determining missing packages.
 # This also means that pip-check-reqs must be installed separately, outside