diff --git a/pr_agent/algo/utils.py b/pr_agent/algo/utils.py
index e38895686..f7a7d686c 100644
--- a/pr_agent/algo/utils.py
+++ b/pr_agent/algo/utils.py
@@ -588,8 +588,8 @@ def load_large_diff(filename, new_file_content_str: str, original_file_content_s
         return ""
 
     try:
-        original_file_content_str = original_file_content_str.rstrip() + "\n"
-        new_file_content_str = new_file_content_str.rstrip() + "\n"
+        original_file_content_str = (original_file_content_str or "").rstrip() + "\n"
+        new_file_content_str = (new_file_content_str or "").rstrip() + "\n"
         diff = difflib.unified_diff(original_file_content_str.splitlines(keepends=True),
                                     new_file_content_str.splitlines(keepends=True))
         if get_settings().config.verbosity_level >= 2 and show_warning: