diff --git a/lib/ui/dart_runtime_hooks.cc b/lib/ui/dart_runtime_hooks.cc
index b1e64bcc0..5041b87c1 100644
--- a/lib/ui/dart_runtime_hooks.cc
+++ b/lib/ui/dart_runtime_hooks.cc
@@ -88,9 +88,9 @@ static void InitDartInternal(Dart_Handle builtin_library, bool is_ui_isolate) {
 }
 
 static void InitDartCore(Dart_Handle builtin, const std::string& script_uri) {
-  DART_CHECK_VALID(
-      Dart_SetField(builtin, ToDart("_baseURL"), ToDart(script_uri)));
-  Dart_Handle get_base_url = GetClosure(builtin, "_getGetBaseURLClosure");
+  Dart_Handle io_lib = Dart_LookupLibrary(ToDart("dart:io"));
+  Dart_Handle get_base_url =
+      Dart_Invoke(io_lib, ToDart("_getUriBaseClosure"), 0, NULL);
   Dart_Handle core_library = Dart_LookupLibrary(ToDart("dart:core"));
   DART_CHECK_VALID(
       Dart_SetField(core_library, ToDart("_uriBaseClosure"), get_base_url));
diff --git a/lib/ui/natives.dart b/lib/ui/natives.dart
index 380a44d1d..b5123099a 100644
--- a/lib/ui/natives.dart
+++ b/lib/ui/natives.dart
@@ -37,15 +37,11 @@ void _setupHooks() {
 
 void _scheduleMicrotask(void callback()) native 'ScheduleMicrotask';
 
-String _baseURL;
-Uri _getBaseURL() => Uri.parse(_baseURL);
-
 // Required for gen_snapshot to work correctly.
 int _isolateId;
 
 Function _getPrintClosure() => _print;
 Function _getScheduleMicrotaskClosure() => _scheduleMicrotask;
-Function _getGetBaseURLClosure() => _getBaseURL;
 
 // Though the "main" symbol is not included in any of the libraries imported
 // above, the builtin library will be included manually during VM setup. This
diff --git a/runtime/dart_vm_entry_points.txt b/runtime/dart_vm_entry_points.txt
index edfae90cf..008272e3f 100644
--- a/runtime/dart_vm_entry_points.txt
+++ b/runtime/dart_vm_entry_points.txt
@@ -1,5 +1,6 @@
 dart:_internal,::,_printClosure
 dart:async,::,_setScheduleImmediateClosure
+dart:io,::,_getUriBaseClosure
 dart:io,::,_setupHooks
 dart:io,_Platform,_localeClosure
 dart:io,_Platform,set:_nativeScript
@@ -11,8 +12,6 @@ dart:ui,::,_dispatchPlatformMessage
 dart:ui,::,_dispatchPointerDataPacket
 dart:ui,::,_dispatchSemanticsAction
 dart:ui,::,_drawFrame
-dart:ui,::,_getGetBaseURLClosure
-dart:ui,::,_baseURL
 dart:ui,::,_getLocaleClosure
 dart:ui,::,_getMainClosure
 dart:ui,::,_getPrintClosure