diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 441445927e..3b5f6bfc2d 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -6118,3 +6118,32 @@ MarkSubTransactionAssigned(void)
 
 	CurrentTransactionState->assigned = true;
 }
+
+/*
+ * CallXactStartCommand
+ *
+ * Wrapper over CallXactCallbacks or CallSubXactCallbacks called in postgres.c
+ * at end of start_xact_command(). It allows to user-defined code to be executed
+ * for the start of any command through a xact registered callback. This function
+ * do nothing if a transaction is not started.
+ *
+ * The related events XactEvent/SubXactEvent are XACT_EVENT_COMMAND_START and
+ * SUBXACT_EVENT_COMMAND_START.
+ */
+void
+CallXactStartCommand(void)
+{
+	TransactionState s = CurrentTransactionState;
+
+	if (s->blockState == TBLOCK_DEFAULT || s->blockState == TBLOCK_STARTED)
+		return;
+
+	/*
+	 * Call start-of-xact callbacks with start command event
+	 */
+	if (s->parent && s->subTransactionId)
+		CallSubXactCallbacks(SUBXACT_EVENT_COMMAND_START, s->subTransactionId,
+							 s->parent->subTransactionId);
+	else
+		CallXactCallbacks(XACT_EVENT_COMMAND_START);
+}
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 8cea10c901..a0f4a17c51 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -2708,6 +2708,16 @@ start_xact_command(void)
 		!get_timeout_active(CLIENT_CONNECTION_CHECK_TIMEOUT))
 		enable_timeout_after(CLIENT_CONNECTION_CHECK_TIMEOUT,
 							 client_connection_check_interval);
+
+	/*
+	 * Instruct registered callbacks on xact that a new command is to be
+	 * executed. It allows to execute user-defined code before any new
+	 * statement is executed. This is the responsability of the user code
+	 * to take care of the state of the transaction, it can be in an ABORT
+	 * state. The related xact events are XACT_EVENT_COMMAND_START and
+	 * SUBXACT_EVENT_COMMAND_START.
+	 */
+	CallXactStartCommand();
 }
 
 static void
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 134f6862da..190fc7151b 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -119,7 +119,8 @@ typedef enum
 	XACT_EVENT_PREPARE,
 	XACT_EVENT_PRE_COMMIT,
 	XACT_EVENT_PARALLEL_PRE_COMMIT,
-	XACT_EVENT_PRE_PREPARE
+	XACT_EVENT_PRE_PREPARE,
+	XACT_EVENT_COMMAND_START
 } XactEvent;
 
 typedef void (*XactCallback) (XactEvent event, void *arg);
@@ -129,7 +130,8 @@ typedef enum
 	SUBXACT_EVENT_START_SUB,
 	SUBXACT_EVENT_COMMIT_SUB,
 	SUBXACT_EVENT_ABORT_SUB,
-	SUBXACT_EVENT_PRE_COMMIT_SUB
+	SUBXACT_EVENT_PRE_COMMIT_SUB,
+	SUBXACT_EVENT_COMMAND_START
 } SubXactEvent;
 
 typedef void (*SubXactCallback) (SubXactEvent event, SubTransactionId mySubid,
@@ -467,4 +469,6 @@ extern void EnterParallelMode(void);
 extern void ExitParallelMode(void);
 extern bool IsInParallelMode(void);
 
+extern void CallXactStartCommand(void);
+
 #endif							/* XACT_H */