diff --git a/qubesadmin/firewall.py b/qubesadmin/firewall.py
index d86f8f4..3a75678 100644
--- a/qubesadmin/firewall.py
+++ b/qubesadmin/firewall.py
@@ -74,6 +74,15 @@ class Action(RuleChoice):
         return 'action=' + str(self)
 
 
+class ForwardType(RuleOption):
+    external = 'external'
+    internal = 'internal'
+
+    @property
+    def rule(self):
+        return 'forwardtype=' + str(self)
+
+
 class Proto(RuleChoice):
     '''Protocol name'''
     tcp = 'tcp'