diff --git a/modules/image/image.module b/modules/image/image.module
index a2a0f41..fac8de95 100644
--- a/modules/image/image.module
+++ b/modules/image/image.module
@@ -1027,7 +1027,15 @@ function image_style_url($style_name, $path) {
   // The token query is added even if the 'image_allow_insecure_derivatives'
   // variable is TRUE, so that the emitted links remain valid if it is changed
   // back to the default FALSE.
-  $token_query = array(IMAGE_DERIVATIVE_TOKEN => image_style_path_token($style_name, $original_uri));
+  // However, sites which need to prevent the token query from being emitted at
+  // all can additionally set the 'image_suppress_itok_output' variable to TRUE
+  // to achieve that (if both are set, the security token will neither be
+  // emitted in the image derivative URL nor checked for in
+  // image_style_deliver()).
+  $token_query = array();
+  if (!variable_get('image_suppress_itok_output', FALSE)) {
+    $token_query = array(IMAGE_DERIVATIVE_TOKEN => image_style_path_token($style_name, $original_uri));
+  }
 
   // If not using clean URLs, the image derivative callback is only available
   // with the query string. If the file does not exist, use url() to ensure
@@ -1039,8 +1047,12 @@ function image_style_url($style_name, $path) {
   }
 
   $file_url = file_create_url($uri);
-  // Append the query string with the token.
-  return $file_url . (strpos($file_url, '?') !== FALSE ? '&' : '?') . drupal_http_build_query($token_query);
+  // Append the query string with the token, if necessary.
+  if ($token_query) {
+    $file_url .= (strpos($file_url, '?') !== FALSE ? '&' : '?') . drupal_http_build_query($token_query);
+  }
+
+  return $file_url;
 }
 
 /**
diff --git a/modules/image/image.test b/modules/image/image.test
index 2387314..3591979 100644
--- a/modules/image/image.test
+++ b/modules/image/image.test
@@ -330,6 +330,15 @@ class ImageStylesPathAndUrlTestCase extends DrupalWebTestCase {
     $this->drupalGet($nested_url);
     $this->assertResponse(200, 'Image was accessible when a correct token was provided in the URL.');
 
+    // Suppress the security token in the URL, then get the URL of a file. Check
+    // that the security token is not present in the URL but that the image is
+    // still accessible.
+    variable_set('image_suppress_itok_output', TRUE);
+    $generate_url = image_style_url($this->style_name, $original_uri);
+    $this->assertIdentical(strpos($generate_url, IMAGE_DERIVATIVE_TOKEN . '='), FALSE, 'The security token does not appear in the image style URL.');
+    $this->drupalGet($generate_url);
+    $this->assertResponse(200, 'Image was accessible at the URL with a missing token.');
+
     // Check that requesting a nonexistent image does not create any new
     // directories in the file system.
     $directory = $scheme . '://styles/' . $this->style_name . '/' . $scheme . '/' . $this->randomName();