diff --git a/src/calibre/utils/fonts/subset.py b/src/calibre/utils/fonts/subset.py
index e41570e664..84d3860b26 100644
--- a/src/calibre/utils/fonts/subset.py
+++ b/src/calibre/utils/fonts/subset.py
@@ -6,10 +6,10 @@ import sys
 from logging.handlers import QueueHandler
 from queue import Empty, SimpleQueue
 
-from fontTools.subset import Subsetter, load_font, log, save_font
 
 
 def subset(input_file_object_or_path, output_file_object_or_path, container_type, chars_or_text=''):
+    from fontTools.subset import Subsetter, load_font, log, save_font
     log_messages = SimpleQueue()
     log_handler = QueueHandler(log_messages)
     log.addHandler(log_handler)