diff --git a/include/mqtt_client.h b/include/mqtt_client.h
index d8c69d2..07dd978 100644
--- a/include/mqtt_client.h
+++ b/include/mqtt_client.h
@@ -318,6 +318,25 @@ int esp_mqtt_client_unsubscribe(esp_mqtt_client_handle_t client, const char *top
  */
 int esp_mqtt_client_publish(esp_mqtt_client_handle_t client, const char *topic, const char *data, int len, int qos, int retain);
 
+/**
+ * @brief Enqueue a message (with qos set to 1 or 2) to the outbox, to be sent later.
+ *
+ * This API generates and stores the publish message into the internal outbox and the actual sending
+ * to the network is performed in the mqtt-task context (in contrast to the esp_mqtt_client_publish()
+ * which sends the publish message immediately in the user task's context).
+ * Thus, it could be used as a non blocking version of esp_mqtt_client_publish().
+ *
+ * @param client    mqtt client handle
+ * @param topic     topic string
+ * @param data      payload string (set to NULL, sending empty payload message)
+ * @param len       data length, if set to 0, length is calculated from payload string
+ * @param qos       qos of publish message, this API is applicable only to qos=1 or 2
+ * @param retain    retain flag
+ *
+ * @return message_id if queued successfully, -1 otherwise
+ */
+int esp_mqtt_client_enqueue(esp_mqtt_client_handle_t client, const char *topic, const char *data, int len, int qos, int retain);
+
 /**
  * @brief Destroys the client handle
  *
diff --git a/mqtt_client.c b/mqtt_client.c
index f2d6557..651515c 100644
--- a/mqtt_client.c
+++ b/mqtt_client.c
@@ -1609,10 +1609,9 @@ int esp_mqtt_client_unsubscribe(esp_mqtt_client_handle_t client, const char *top
     return client->mqtt_state.pending_msg_id;
 }
 
-int esp_mqtt_client_publish(esp_mqtt_client_handle_t client, const char *topic, const char *data, int len, int qos, int retain)
+static inline int mqtt_client_enqueue_priv(esp_mqtt_client_handle_t client, const char *topic, const char *data, int len, int qos, int retain)
 {
     uint16_t pending_msg_id = 0;
-    int ret = 0;
 
     /* Acceptable publish messages:
         data == NULL, len == 0: publish null message
@@ -1623,15 +1622,13 @@ int esp_mqtt_client_publish(esp_mqtt_client_handle_t client, const char *topic,
         len = strlen(data);
     }
 
-    MQTT_API_LOCK(client);
     mqtt_message_t *publish_msg = mqtt_msg_publish(&client->mqtt_state.mqtt_connection,
-                                  topic, data, len,
-                                  qos, retain,
-                                  &pending_msg_id);
+                                                   topic, data, len,
+                                                   qos, retain,
+                                                   &pending_msg_id);
 
     if (publish_msg->length == 0) {
         ESP_LOGE(TAG, "Publish message cannot be created");
-        MQTT_API_UNLOCK(client);
         return -1;
     }
     /* We have to set as pending all the qos>0 messages */
@@ -1647,8 +1644,21 @@ int esp_mqtt_client_publish(esp_mqtt_client_handle_t client, const char *topic,
         } else {
             int first_fragment = client->mqtt_state.outbound_message->length - client->mqtt_state.outbound_message->fragmented_msg_data_offset;
             mqtt_enqueue_oversized(client, ((uint8_t *)data) + first_fragment, len - first_fragment);
+            client->mqtt_state.outbound_message->fragmented_msg_total_length = 0;
         }
     }
+    return pending_msg_id;
+}
+
+int esp_mqtt_client_publish(esp_mqtt_client_handle_t client, const char *topic, const char *data, int len, int qos, int retain)
+{
+    MQTT_API_LOCK(client);
+    int pending_msg_id = mqtt_client_enqueue_priv(client, topic, data, len, qos, retain);
+    if (pending_msg_id < 0) {
+        MQTT_API_UNLOCK(client);
+        return -1;
+    }
+    int ret = 0;
 
     /* Skip sending if not connected (rely on resending) */
     if (client->state != MQTT_STATE_CONNECTED) {
@@ -1657,7 +1667,7 @@ int esp_mqtt_client_publish(esp_mqtt_client_handle_t client, const char *topic,
             ret = pending_msg_id;
         }
 
-        //Delete message after OUTBOX_EXPIRED_TIMEOUT_MS miliseconds
+        // Delete message after OUTBOX_EXPIRED_TIMEOUT_MS milliseconds
         int deleted = outbox_delete_expired(client->outbox, platform_tick_get_ms(), OUTBOX_EXPIRED_TIMEOUT_MS);
         client->mqtt_state.pending_msg_count -= deleted;
 
@@ -1727,6 +1737,17 @@ cannot_publish:
     return ret;
 }
 
+int esp_mqtt_client_enqueue(esp_mqtt_client_handle_t client, const char *topic, const char *data, int len, int qos, int retain)
+{
+    MQTT_API_LOCK(client);
+    int ret = mqtt_client_enqueue_priv(client, topic, data, len, qos, retain);
+    MQTT_API_UNLOCK(client);
+    if (ret == 0) {
+        // messages with qos=0 are not enqueued -> indicate as error
+        return -1;
+    }
+    return ret;
+}
 
 esp_err_t esp_mqtt_client_register_event(esp_mqtt_client_handle_t client, esp_mqtt_event_id_t event, esp_event_handler_t event_handler, void* event_handler_arg)
 {