diff --git a/pkg/dart2wasm/lib/translator.dart b/pkg/dart2wasm/lib/translator.dart
index d39958f4cb9..b1e5cdb12b2 100644
--- a/pkg/dart2wasm/lib/translator.dart
+++ b/pkg/dart2wasm/lib/translator.dart
@@ -1860,13 +1860,13 @@ class Translator with KernelNodes {
       // runtime.
       final i = internalizedStringsForJSRuntime.length;
       internalizedString = module.globals.import('s', '$i',
-          w.GlobalType(w.RefType.extern(nullable: true), mutable: false));
+          w.GlobalType(w.RefType.extern(nullable: false), mutable: false));
       internalizedStringsForJSRuntime.add(s);
     } else {
       internalizedString = module.globals.import(
         'S',
         s,
-        w.GlobalType(w.RefType.extern(nullable: true), mutable: false),
+        w.GlobalType(w.RefType.extern(nullable: false), mutable: false),
       );
     }
     _internalizedStringGlobals[(module, s)] = internalizedString;
diff --git a/pkg/dart2wasm/test/ir_tests/deferred.constant.wat b/pkg/dart2wasm/test/ir_tests/deferred.constant.wat
index d9f9f943f8f..2e3a54604a1 100644
--- a/pkg/dart2wasm/test/ir_tests/deferred.constant.wat
+++ b/pkg/dart2wasm/test/ir_tests/deferred.constant.wat
@@ -25,8 +25,8 @@
     (field $fun (ref $#Closure-0-1)))))
   (type $type256 <...>)
   (type $#DummyStruct <...>)
-  (global $S.globalH1Bar< (import "S" "globalH1Bar<") externref)
-  (global $S.globalH0Foo (import "S" "globalH0Foo") externref)
+  (global $S.globalH1Bar< (import "S" "globalH1Bar<") (ref extern))
+  (global $S.globalH0Foo (import "S" "globalH0Foo") (ref extern))
   (global $global29 (ref $#DummyStruct) <...>)
   (global $"C28 _InterfaceType" (ref $_InterfaceType) <...>)
   (global $"C334 \"h0\"" (ref $JSStringImpl) <...>)
diff --git a/pkg/dart2wasm/test/ir_tests/hello.wat b/pkg/dart2wasm/test/ir_tests/hello.wat
index e94dde2d52f..6b9c5277f06 100644
--- a/pkg/dart2wasm/test/ir_tests/hello.wat
+++ b/pkg/dart2wasm/test/ir_tests/hello.wat
@@ -4,7 +4,7 @@
   (type $JSStringImpl (sub final $#Top (struct
     (field $field0 i32)
     (field $_ref externref))))
-  (global $"S.hello world" (import "S" "hello world") externref)
+  (global $"S.hello world" (import "S" "hello world") (ref extern))
   (global $"C329 \"hello world\"" (ref $JSStringImpl)
     (i32.const 4)
     (global.get $"S.hello world")