diff --git a/package.json b/package.json
index a8623bd54d3..fe4832eefd4 100644
--- a/package.json
+++ b/package.json
@@ -4,8 +4,8 @@
     "scripts": {
         "build": "lerna run build",
         "watch": "lerna run --parallel watch",
-        "test-unit": "cross-env NODE_ENV=test cross-env BABEL_ENV=cjs NODE_ICU_DATA=./node_modules/full-icu jest",
-        "test-unit-ci": "cross-env NODE_ENV=test cross-env BABEL_ENV=cjs NODE_ICU_DATA=./node_modules/full-icu jest --runInBand",
+        "test-unit": "cross-env LANG=en_US.UTF-8 NODE_ENV=test cross-env BABEL_ENV=cjs NODE_ICU_DATA=./node_modules/full-icu jest",
+        "test-unit-ci": "cross-env LANG=en_US.UTF-8 NODE_ENV=test cross-env BABEL_ENV=cjs NODE_ICU_DATA=./node_modules/full-icu jest --runInBand",
         "test-e2e": "yarn run -s build && cross-env NODE_ENV=test && cd cypress && yarn test",
         "test-e2e-local": "cd cypress && yarn start",
         "test": "yarn test-unit && yarn test-e2e",