diff --git a/doc/Addons.md b/doc/Addons.md
index ec82452d5..6fa87c953 100644
--- a/doc/Addons.md
+++ b/doc/Addons.md
@@ -520,6 +520,24 @@ Hook data:
 - **contact** (input): the remote contact (uid = local revoking user id) array.
 - **result** (output): a boolean value indicating wether the operation was successful or not.
 
+### block
+
+Called when blocking a remote contact on a non-native network (like Twitter).
+
+Hook data:
+- **contact** (input): the remote contact (uid = 0) array.
+- **uid** (input): the user id to issue the block for.
+- **result** (output): a boolean value indicating wether the operation was successful or not.
+
+### unblock
+
+Called when unblocking a remote contact on a non-native network (like Twitter).
+
+Hook data:
+- **contact** (input): the remote contact (uid = 0) array.
+- **uid** (input): the user id to revoke the block for.
+- **result** (output): a boolean value indicating wether the operation was successful or not.
+
 ## Complete list of hook callbacks
 
 Here is a complete list of all hook callbacks with file locations (as of 24-Sep-2018). Please see the source for details of any hooks not documented above.
@@ -777,7 +795,9 @@ Here is a complete list of all hook callbacks with file locations (as of 24-Sep-
     Hook::callAll('support_follow', $hook_data);
     Hook::callAll('support_revoke_follow', $hook_data);
     Hook::callAll('unfollow', $hook_data);
-    Kook::callAll('revoke_follow', $hook_data);
+    Hook::callAll('revoke_follow', $hook_data);
+    Hook::callAll('block', $hook_data);
+    Hook::callAll('unblock', $hook_data);
 
 ### src/Core/StorageManager
 
diff --git a/doc/de/Addons.md b/doc/de/Addons.md
index e7fecc29a..64e3e37ba 100644
--- a/doc/de/Addons.md
+++ b/doc/de/Addons.md
@@ -418,7 +418,9 @@ Eine komplette Liste aller Hook-Callbacks mit den zugehörigen Dateien (am 01-Ap
     Hook::callAll('support_follow', $hook_data);
     Hook::callAll('support_revoke_follow', $hook_data);
     Hook::callAll('unfollow', $hook_data);
-    Kook::callAll('revoke_follow', $hook_data);
+    Hook::callAll('revoke_follow', $hook_data);
+    Hook::callAll('block', $hook_data);
+    Hook::callAll('unblock', $hook_data);
 
 ### src/Core/StorageManager
 
diff --git a/src/Core/Protocol.php b/src/Core/Protocol.php
index 66c74ccc9..a01e632bf 100644
--- a/src/Core/Protocol.php
+++ b/src/Core/Protocol.php
@@ -287,4 +287,46 @@ class Protocol
 
 		return $hook_data['result'];
 	}
+
+	/**
+	 * Send a block message to a remote server. Only useful for connector addons.
+	 *
+	 * @param array $contact Public contact record to block
+	 * @param int   $uid     User issuing the block
+	 * @return bool|null true if successful, false if not, null if no action was performed
+	 * @throws HTTPException\InternalServerErrorException
+	 */
+	public static function block(array $contact, int $uid): ?bool
+	{
+		// Catch-all hook for connector addons
+		$hook_data = [
+			'contact' => $contact,
+			'uid' => $uid,
+			'result' => null,
+		];
+		Hook::callAll('block', $hook_data);
+
+		return $hook_data['result'];
+	}
+
+	/**
+	 * Send an unblock message to a remote server. Only useful for connector addons.
+	 *
+	 * @param array $contact Public contact record to unblock
+	 * @param int   $uid     User revoking the block
+	 * @return bool|null true if successful, false if not, null if no action was performed
+	 * @throws HTTPException\InternalServerErrorException
+	 */
+	public static function unblock(array $contact, int $uid): ?bool
+	{
+		// Catch-all hook for connector addons
+		$hook_data = [
+			'contact' => $contact,
+			'uid' => $uid,
+			'result' => null,
+		];
+		Hook::callAll('unblock', $hook_data);
+
+		return $hook_data['result'];
+	}
 }
diff --git a/src/Model/Contact/User.php b/src/Model/Contact/User.php
index eb0b5af09..7d6ce17da 100644
--- a/src/Model/Contact/User.php
+++ b/src/Model/Contact/User.php
@@ -23,6 +23,7 @@ namespace Friendica\Model\Contact;
 
 use Exception;
 use Friendica\Core\Logger;
+use Friendica\Core\Protocol;
 use Friendica\Core\System;
 use Friendica\Database\Database;
 use Friendica\Database\DBA;
@@ -145,6 +146,13 @@ class User
 			return;
 		}
 
+		$contact = Contact::getById($cdata['public']);
+		if ($blocked) {
+			Protocol::block($contact);
+		} else {
+			Protocol::unblock($contact);
+		}
+
 		if ($cdata['user'] != 0) {
 			DBA::update('contact', ['blocked' => $blocked], ['id' => $cdata['user'], 'pending' => false]);
 		}