diff --git a/admin/tool/customlang/cli/import.php b/admin/tool/customlang/cli/import.php
index 4daff057fdf..492e466b7ae 100644
--- a/admin/tool/customlang/cli/import.php
+++ b/admin/tool/customlang/cli/import.php
@@ -160,6 +160,16 @@ foreach ($langfiles as $lng => $files) {
 
     cli_heading(get_string('clifiles', 'tool_customlang', $lng));
 
+    // If we intend to check in any changes, we must first check them out.
+    if ($checkin) {
+        cli_writeln(get_string('checkout', 'tool_customlang'));
+
+        $progressbar = new progress_bar();
+        $progressbar->create();
+
+        tool_customlang_utils::checkout($lng, $progressbar);
+    }
+
     foreach ($files as $file) {
         // Generate a valid stored_file from this file.
         $record = (object)[
diff --git a/admin/tool/customlang/locallib.php b/admin/tool/customlang/locallib.php
index 1e7f696e7ac..b4c8c397c18 100644
--- a/admin/tool/customlang/locallib.php
+++ b/admin/tool/customlang/locallib.php
@@ -89,7 +89,9 @@ class tool_customlang_utils {
      * @param progress_bar $progressbar optionally, the given progress bar can be updated
      */
     public static function checkout($lang, progress_bar $progressbar = null) {
-        global $DB;
+        global $DB, $CFG;
+
+        require_once("{$CFG->libdir}/adminlib.php");
 
         // For behat executions we are going to load only a few components in the
         // language customisation structures. Using the whole "en" langpack is