diff --git a/src/objects/js-locale.cc b/src/objects/js-locale.cc
index 98ce154336..6c3f284e71 100644
--- a/src/objects/js-locale.cc
+++ b/src/objects/js-locale.cc
@@ -425,8 +425,13 @@ MaybeHandle<JSLocale> JSLocale::Maximize(Isolate* isolate,
     // Base name is not changed
     result = source;
   }
-  DCHECK(U_SUCCESS(status));
-  DCHECK(!result.isBogus());
+  if (U_FAILURE(status) || result.isBogus()) {
+    // Due to https://unicode-org.atlassian.net/browse/ICU-21639
+    // Valid but super long locale will fail. Just throw here for now.
+    THROW_NEW_ERROR(isolate,
+                    NewRangeError(MessageTemplate::kLocaleBadParameters),
+                    JSLocale);
+  }
   return Construct(isolate, result);
 }
 
@@ -455,8 +460,13 @@ MaybeHandle<JSLocale> JSLocale::Minimize(Isolate* isolate,
     // Base name is not changed
     result = source;
   }
-  DCHECK(U_SUCCESS(status));
-  DCHECK(!result.isBogus());
+  if (U_FAILURE(status) || result.isBogus()) {
+    // Due to https://unicode-org.atlassian.net/browse/ICU-21639
+    // Valid but super long locale will fail. Just throw here for now.
+    THROW_NEW_ERROR(isolate,
+                    NewRangeError(MessageTemplate::kLocaleBadParameters),
+                    JSLocale);
+  }
   return Construct(isolate, result);
 }
 
diff --git a/test/intl/regress-1224869.js b/test/intl/regress-1224869.js
new file mode 100644
index 0000000000..2d30ac5dc5
--- /dev/null
+++ b/test/intl/regress-1224869.js
@@ -0,0 +1,18 @@
+// Copyright 2021 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+var l = new Intl.Locale("en-US-4106-4104-4102-4100-4098-4096-4094-4092-4090-4088-4086-4084-4082-4080-4078-4076-4074-4072-4070-4068-4066-4064-4062-4060-4058-4056-4054-4052-4050-4048-4049");
+
+// Ensure won't DCHECK in debug build
+try {
+  l.maximize();
+} catch(e) {
+}
+
+l2 = new Intl.Locale("en-US-4106-4104-4102-4100-4098-4096-4094-4092-4090-4088-4086-4084-4082-4080-4078-4076-4074-4072-4070-4068-4066-4064-4062-4060-4058-4056-4054-4052-4050-4048-4049");
+// Ensure won't DCHECK in debug build
+try {
+  l2.minimize();
+} catch(e) {
+}