diff --git a/Trigger/TriggerCommon/TriggerMenuMT/python/HLTMenuConfig/CalibCosmicMon/MonitorChainConfiguration.py b/Trigger/TriggerCommon/TriggerMenuMT/python/HLTMenuConfig/CalibCosmicMon/MonitorChainConfiguration.py
index ae73411fa2e2e717527fbbb077d72194327e17a5..08fd2b044ccc697ffbcee88fb0ebb4308881b173 100644
--- a/Trigger/TriggerCommon/TriggerMenuMT/python/HLTMenuConfig/CalibCosmicMon/MonitorChainConfiguration.py
+++ b/Trigger/TriggerCommon/TriggerMenuMT/python/HLTMenuConfig/CalibCosmicMon/MonitorChainConfiguration.py
@@ -100,7 +100,10 @@ class MonitorChainConfiguration(ChainConfigurationBase):
         if monType == 'timeburner':
             chainSteps.append(self.getTimeBurnerStep())
         elif monType == 'l1topodebug':
-            chainSteps.append(self.getL1TopoOnlineMonitorStep())
+            if ConfigFlags.Trigger.enableL1MuonPhase1:
+                chainSteps.append(self.getL1TopoOnlineMonitorStep())
+            else:
+                log.warning('Not adding chain %s. L1Topo monitoring only supported with Phase-1 MUCTPI (ATR-24179)', self.chainName)
         else:
             raise RuntimeError('Unexpected monType '+monType+' in MonitorChainConfiguration')