diff --git a/tools/tox_install.sh b/tools/tox_install.sh
index 0520fed..734f922 100755
--- a/tools/tox_install.sh
+++ b/tools/tox_install.sh
@@ -5,7 +5,7 @@
 # the constraints file before applying it for from-source installation.
 
 ZUUL_CLONER=/usr/zuul-env/bin/zuul-cloner
-BRANCH_NAME=master
+BRANCH_NAME=stable/newton
 CLIENT_NAME=python-monascaclient
 requirements_installed=$(echo "import openstack_requirements" | python 2>/dev/null ; echo $?)
 
diff --git a/tox.ini b/tox.ini
index 48aae5e..b627459 100644
--- a/tox.ini
+++ b/tox.ini
@@ -7,7 +7,7 @@ skipsdist = True
 setenv = VIRTUAL_ENV={envdir}
 usedevelop = True
 install_command =
-    {toxinidir}/tools/tox_install.sh {env:UPPER_CONSTRAINTS_FILE:https://git.openstack.org/cgit/openstack/requirements/plain/upper-constraints.txt} {opts} {packages}
+    {toxinidir}/tools/tox_install.sh {env:UPPER_CONSTRAINTS_FILE:https://git.openstack.org/cgit/openstack/requirements/plain/upper-constraints.txt?h=stable/newton} {opts} {packages}
 deps = -r{toxinidir}/requirements.txt
        -r{toxinidir}/test-requirements.txt
 whitelist_externals = find