diff --git a/unittest/correct-loopback.yaml b/unittest/correct-loopback.yaml
index be780cc..c78e968 100644
--- a/unittest/correct-loopback.yaml
+++ b/unittest/correct-loopback.yaml
@@ -10,11 +10,6 @@ loopbacks:
     mtu: 9216
     addresses: [ 192.0.2.1/29 ]
 
-  loop10:
-    description: "Loopback instance loop10, with address, but no LCP"
-    mtu: 9216
-    addresses: [ 192.0.2.1/29 ]
-
   loop20:
     description: "Loopback instance loop20, with LCP, but no address"
     mtu: 9216
diff --git a/unittest/error-loopback1.yaml b/unittest/error-loopback1.yaml
new file mode 100644
index 0000000..e427da1
--- /dev/null
+++ b/unittest/error-loopback1.yaml
@@ -0,0 +1,12 @@
+test:
+  description: "Cannot give an IP address to a loopback without LCP"
+  errors:
+    expected:
+     - "loopback .* has an address but no LCP"
+    count: 1
+---
+loopbacks:
+  loop10:
+    description: "Loopback instance loop10, with address, but no LCP"
+    mtu: 9216
+    addresses: [ 192.0.2.1/29 ]
diff --git a/validator/loopback.py b/validator/loopback.py
index 381e46b..0acbee3 100644
--- a/validator/loopback.py
+++ b/validator/loopback.py
@@ -26,4 +26,8 @@ def validate_loopbacks(yaml):
     logger.debug("Validating loopbacks...")
     for ifname, iface in yaml['loopbacks'].items():
         logger.debug("loopback %s" % iface)
+        if 'addresses' in iface and not 'lcp' in iface:
+            msgs.append("loopback %s has an address but no LCP" % ifname)
+            result = False
+
     return result, msgs