diff --git a/classes/State.php b/classes/State.php
index 2a500ab5f..9ca4fccb1 100644
--- a/classes/State.php
+++ b/classes/State.php
@@ -113,13 +113,13 @@ class StateCore extends ObjectModel
 	* @param string $iso_code Iso code
 	* @return integer state id
 	*/
-	public static function getIdByIso($iso_code)
+	public static function getIdByIso($iso_code, $id_country = null)
 	{
 	  	return Db::getInstance()->getValue('
-			SELECT `id_state`
-			FROM `'._DB_PREFIX_.'state`
-			WHERE `iso_code` = \''.pSQL($iso_code).'\''
-		);
+		SELECT `id_state`
+		FROM `'._DB_PREFIX_.'state`
+		WHERE `iso_code` = \''.pSQL($iso_code).'\'
+		'.($id_country ? 'AND `id_country` = '.(int)$id_country : ''));
 	}
 
 	/**
diff --git a/controllers/admin/AdminStatesController.php b/controllers/admin/AdminStatesController.php
index 93abf400d..7987cd44b 100644
--- a/controllers/admin/AdminStatesController.php
+++ b/controllers/admin/AdminStatesController.php
@@ -181,6 +181,18 @@ class AdminStatesControllerCore extends AdminController
 	{
 		if (!isset($this->table))
 			return false;
+			
+		if (!Tools::getValue('id_'.$this->table))
+		{
+			if (Validate::isStateIsoCode(Tools::getValue('iso_code')) && State::getIdByIso(Tools::getValue('iso_code'), Tools::getValue('id_country')))
+				$this->errors[] = Tools::displayError('This ISO code already exists, you cannot create two states with the same ISO code in the same country');
+		}
+		else if (Validate::isStateIsoCode(Tools::getValue('iso_code')))
+		{
+			$id_state = State::getIdByIso(Tools::getValue('iso_code'), Tools::getValue('id_country'));
+			if ($id_state && $id_state != Tools::getValue('id_'.$this->table))
+				$this->errors[] = Tools::displayError('This ISO code already exists, you cannot create two states with the same ISO code in the same country');
+		}
 
 		/* Delete object */
 		if (isset($_GET['delete'.$this->table]))