diff --git a/src/mibew/js/source/widget.js b/src/mibew/js/source/widget.js
index 89e8d2b3..32733d39 100644
--- a/src/mibew/js/source/widget.js
+++ b/src/mibew/js/source/widget.js
@@ -78,6 +78,12 @@ var Mibew = Mibew || {};
          */
         this.visitorCookieName = options.visitorCookieName;
 
+        /**
+         * Name of tracking cookie
+         * @type String
+         */
+        this.cookiesBlocked = false;
+
         /**
          * URL of file with additional CSS rules for invitation
          * @type String
@@ -112,7 +118,14 @@ var Mibew = Mibew || {};
         // Prepare GET params list
         this.dataToSend.entry = escape(document.referrer),
         this.dataToSend.locale = this.locale;
+        // Random value should be set both as a GET param and as a cookie,
+        // so it will be possible to find out whether cookies are blocked
+        // Also it will prevent response from being cached at any level
         this.dataToSend.rnd = Math.random();
+        Mibew.Utils.createCookie(
+            'mibewRndValue',
+            this.dataToSend.rnd
+        );
         if (userId !== false) {
             this.dataToSend.user_id = userId;
         } else {
@@ -330,6 +343,12 @@ var Mibew = Mibew || {};
      *  - 'acceptCaption': String, caption for accept button.
      */
     Mibew.Invitation.create = function (options) {
+
+        // Cookies are blocked, invitation will behave badly
+        if (Mibew.Objects.widget.cookiesBlocked) {
+            return;
+        }
+
         var operatorName = options.operatorName;
         var avatarUrl = options.avatarUrl;
         var threadUrl = options.threadUrl;
@@ -481,6 +500,14 @@ var Mibew = Mibew || {};
      */
     Mibew.APIFunctions = {};
 
+    /**
+     * Update cookies status. API function
+     * @param {Object} response Data object from server
+     */
+    Mibew.APIFunctions.updateCookiesBlockStatus = function(response) {
+        Mibew.Objects.widget.cookiesBlocked = response.cookiesBlocked;
+    };
+
     /**
      * Update user id. API function
      * @param {Object} response Data object from server
diff --git a/src/mibew/libs/classes/Mibew/Controller/WidgetController.php b/src/mibew/libs/classes/Mibew/Controller/WidgetController.php
index a77ab5bb..f560286b 100644
--- a/src/mibew/libs/classes/Mibew/Controller/WidgetController.php
+++ b/src/mibew/libs/classes/Mibew/Controller/WidgetController.php
@@ -51,10 +51,31 @@ class WidgetController extends AbstractController
             'data' => array(),
         );
 
+        // Check whether third parties cookies are blocked
+        // It will be impossible to chat if they are
+        $cookies_blocked = false;
+        $rnd_value1 = $request->query->get('rnd', false);
+        if ($request->cookies->has('mibewRndValue')) {
+            $rnd_value2 = $request->cookies->get('mibewRndValue');
+            if ($rnd_value1 !== $rnd_value2) {
+                $cookies_blocked = true;
+            }
+        }
+        else {
+            $cookies_blocked = true;
+        }
+
+        // Update status on blocked cookie
+        $response_data['handlers'][] = 'updateCookiesBlockStatus';
+        $response_data['dependencies']['updateCookiesBlockStatus'] = array();
+        $response_data['data']['cookiesBlocked'] = $cookies_blocked;
+
         $tracking_allowed = (Settings::get('enabletracking') == '1')
-            && (Settings::get('trackoperators') == '1' || !$this->getOperator());
+            && (Settings::get('trackoperators') == '1' || !$this->getOperator())
+            && !$cookies_blocked;
 
         if ($tracking_allowed) {
+
             $entry = $request->query->get('entry', '');
             $referer = $request->server->get('HTTP_REFERER', '');
             $user_id = $request->query->get('user_id', false);