diff --git a/hwe/j_diplomacy_respond_letter.php b/hwe/j_diplomacy_respond_letter.php
index a8e492c7..294f3fc4 100644
--- a/hwe/j_diplomacy_respond_letter.php
+++ b/hwe/j_diplomacy_respond_letter.php
@@ -112,6 +112,17 @@ $msg = new Message(
 );
 $msgID = $msg->send();
 
+$msg = new Message(
+    Message::MSGTYPE_NATIONAL,
+    $src,
+    $dest,
+    $msgText,
+    $now,
+    $unlimited,
+    ['invalid' => true]
+);
+$msgID = $msg->send();
+
 Json::die([
     'result'=>true,
     'reason'=>'success'
diff --git a/hwe/sammo/DiplomaticMessage.php b/hwe/sammo/DiplomaticMessage.php
index 183d2e0a..2bb69009 100644
--- a/hwe/sammo/DiplomaticMessage.php
+++ b/hwe/sammo/DiplomaticMessage.php
@@ -345,6 +345,20 @@ class DiplomaticMessage extends Message{
         $this->invalidate();
         $newMsg->send();
 
+        $newMsg = new Message(
+            self::MSGTYPE_DIPLOMACY, 
+            $this->dest, 
+            $this->src, 
+            "【외교】{$year}년 {$month}월: {$this->src->nationName}{$josaYi} {$this->dest->nationName}에게 제안한 {$this->diplomacyDetail}{$this->diplomacyName} 동의.",
+            new \DateTime(),
+            new \DateTime('9999-12-31'),
+            [
+                'delete'=>$this->id,
+                'silence'=>true,
+            ]
+        );
+        $newMsg->send();
+
         return self::ACCEPTED;
 
     }