diff --git a/lib/worldwide/config.rb b/lib/worldwide/config.rb
index 7409018a6..5da64a014 100644
--- a/lib/worldwide/config.rb
+++ b/lib/worldwide/config.rb
@@ -39,8 +39,7 @@ def configure_i18n(i18n_config: nil, additional_components: [])
 
         set_unless_explicitly_set(i18n_config, :default_locale, :en)
         set_unless_explicitly_set(i18n_config, :exception_handler, exception_handler)
-
-        i18n_config.available_locales = expanded_locales_from_configuration(i18n_config)
+        set_unless_explicitly_set(i18n_config, :available_locales, expanded_locales_from_configuration(i18n_config))
 
         add_cldr_data(i18n_config, additional_components: additional_components)
         add_other_data(i18n_config)