diff --git a/Core/src/ClientTrait.php b/Core/src/ClientTrait.php
index 1f6e5cd5f24..3f25e88875b 100644
--- a/Core/src/ClientTrait.php
+++ b/Core/src/ClientTrait.php
@@ -182,8 +182,7 @@ private function detectProjectId(array $config)
             'projectId' => null,
             'projectIdRequired' => false,
             'hasEmulator' => false,
-            'preferNumericProjectId' => false,
-            'suppressKeyFileNotice' => false
+            'preferNumericProjectId' => false
         ];
 
         if ($config['projectId']) {
@@ -202,23 +201,6 @@ private function detectProjectId(array $config)
             if (isset($config['keyFile']['project_id'])) {
                 return $config['keyFile']['project_id'];
             }
-
-            if ($config['suppressKeyFileNotice'] !== true) {
-                $serviceAccountUri = 'https://cloud.google.com/iam/docs/' .
-                    'creating-managing-service-account-keys#creating_service_account_keys';
-
-                trigger_error(
-                    sprintf(
-                        'A keyfile was given, but it does not contain a project ' .
-                        'ID. This can indicate an old and obsolete keyfile, ' .
-                        'in which case you should create a new one. To suppress ' .
-                        'this message, set `suppressKeyFileNotice` to `true` in your client configuration. ' .
-                        'To learn more about generating new keys, see this URL: %s',
-                        $serviceAccountUri
-                    ),
-                    E_USER_NOTICE
-                );
-            }
         }
 
         if (getenv('GOOGLE_CLOUD_PROJECT')) {
diff --git a/Core/tests/Unit/ClientTraitTest.php b/Core/tests/Unit/ClientTraitTest.php
index 5d9a28ef2a5..867497fe3dd 100644
--- a/Core/tests/Unit/ClientTraitTest.php
+++ b/Core/tests/Unit/ClientTraitTest.php
@@ -358,33 +358,6 @@ public function testDetectProjectIdEmulator()
 
         $this->assertEquals($projectId, $res);
     }
-
-    public function testDetectProjectIdWithKeyfileMissingProjectId()
-    {
-        set_error_handler(static function (int $errno, string $errstr): never {
-            throw new Exception($errstr, $errno);
-        }, E_USER_NOTICE);
-        $this->expectException(Exception::class);
-        $this->expectExceptionMessage('A keyfile was given');
-
-        $trait = TestHelpers::impl(ClientTrait::class);
-
-        $res = $trait->call('detectProjectId', [[
-            'keyFile' => []
-        ]]);
-    }
-
-    public function testDetectProjectIdWithKeyfileMissingProjectIdSuppressNotice()
-    {
-        $trait = TestHelpers::impl(ClientTraitStubOnGceReturnsFalse::class);
-
-        $res = $trait->call('detectProjectId', [[
-            'keyFile' => [],
-            'suppressKeyFileNotice' => true
-        ]]);
-
-        $this->assertTrue(true);
-    }
 }
 
 //@codingStandardsIgnoreStart