diff --git a/packages/ui/src/index.tsx b/packages/ui/src/index.tsx
index 94cf0193..b708f6ec 100644
--- a/packages/ui/src/index.tsx
+++ b/packages/ui/src/index.tsx
@@ -18,7 +18,7 @@ const uiConfig = JSON.parse(
   document.getElementById('__UI_CONFIG__')?.textContent || '{}'
 ) as UIConfig;
 
-initI18n({ lng: uiConfig.locale?.lng || 'en', basePath }).then(() => {
+initI18n({ lng: uiConfig.locale?.lng || 'en-US', basePath }).then(() => {
   render(
     <BrowserRouter basename={basePath}>
       <UIConfigContext.Provider value={uiConfig}>
diff --git a/packages/ui/src/services/i18n.ts b/packages/ui/src/services/i18n.ts
index 12de3d2a..03ba414a 100644
--- a/packages/ui/src/services/i18n.ts
+++ b/packages/ui/src/services/i18n.ts
@@ -16,13 +16,13 @@ export async function initI18n({ lng, basePath }: { lng: string; basePath: strin
     i18nextInstance.use(new HMRPlugin({ webpack: { client: true } }));
     (window as any).testI18n = (lng = 'cimode') => i18nextInstance.changeLanguage(lng);
   }
-  const locale = lng === 'en' ? 'en-US' : lng;
-  dateFnsLocale = await import(`date-fns/locale/${locale}/index.js`).catch((e) => console.error(e));
+  dateFnsLocale = await import(`date-fns/locale/${lng}/index.js`).catch((e) => console.error(e));
   return i18nextInstance.init({
     lng,
-    fallbackLng: 'en',
+    fallbackLng: 'en-US',
     defaultNS: 'messages',
     ns: 'messages',
+    load: 'currentOnly',
     backend: {
       loadPath: `${basePath}static/locales/{{lng}}/{{ns}}.json`,
       queryParams: { v: process.env.APP_VERSION },
diff --git a/packages/ui/src/static/locales/en/messages.json b/packages/ui/src/static/locales/en-US/messages.json
similarity index 100%
rename from packages/ui/src/static/locales/en/messages.json
rename to packages/ui/src/static/locales/en-US/messages.json