diff --git a/gradle.properties b/gradle.properties
index 8a9ca19d4f..27af3d1328 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -1 +1,2 @@
-org.gradle.jvmargs=-Xmx1g -XX:MaxMetaspaceSize=512m -XX:+HeapDumpOnOutOfMemoryError -Duser.language=en
\ No newline at end of file
+# Keep system properties in sync with test system properties (java-module.gradle)!
+org.gradle.jvmargs=-Xmx1g -XX:MaxMetaspaceSize=512m -XX:+HeapDumpOnOutOfMemoryError -Duser.language=en -Duser.country=US -Duser.timezone=UTC -Dfile.encoding=UTF-8
diff --git a/gradle/java-module.gradle b/gradle/java-module.gradle
index 175f41a825..b2ac9142f4 100644
--- a/gradle/java-module.gradle
+++ b/gradle/java-module.gradle
@@ -201,7 +201,15 @@ processTestResources {
 	}
 }
 
-// Enable the experimental features of ByteBuddy with JDK 12+
+// Keep system properties in sync with gradle.properties!
+test {
+	systemProperty 'user.language', 'en'
+	systemProperty 'user.country', 'US'
+	systemProperty 'user.timezone', 'UTC'
+	systemProperty 'file.encoding', 'UTF-8'
+}
+
+// Enable the experimental features of ByteBuddy with JDK 15+
 test {
 	//Only safe to attempt to parse the version as an integer since JDK11
 	if ( JavaVersion.current().isJava11Compatible() ) {