diff --git a/vector/src/main/java/im/vector/app/features/home/room/detail/RoomDetailViewState.kt b/vector/src/main/java/im/vector/app/features/home/room/detail/RoomDetailViewState.kt
index 0c56d7e7eb..e01c5ba3b7 100644
--- a/vector/src/main/java/im/vector/app/features/home/room/detail/RoomDetailViewState.kt
+++ b/vector/src/main/java/im/vector/app/features/home/room/detail/RoomDetailViewState.kt
@@ -87,7 +87,12 @@ data class RoomDetailViewState(
             rootThreadEventId = args.threadTimelineArgs?.rootThreadEventId
     )
 
-    fun isCallOptionAvailable() = asyncRoomSummary.invoke()?.isDirect ?: true
+    fun isCallOptionAvailable(): Boolean {
+        return asyncRoomSummary.invoke()?.isDirect ?: true ||
+                // When there is only one member, a warning will be displayed when the user
+                // clicks on the menu item to start a call
+                asyncRoomSummary.invoke()?.joinedMembersCount == 1
+    }
 
     fun isSearchAvailable() = asyncRoomSummary()?.isEncrypted == false