diff --git a/src/poetry/packages/locker.py b/src/poetry/packages/locker.py
index 649b4197c63..80177f16dd3 100644
--- a/src/poetry/packages/locker.py
+++ b/src/poetry/packages/locker.py
@@ -290,8 +290,6 @@ def _should_write(self, lock: TOMLDocument) -> bool:
         return do_write
 
     def _write_lock_data(self, data: TOMLDocument) -> None:
-        lockfile = TOMLFile(self.lock)
-
         if self.lock.exists():
             # The following code is roughly equivalent to
             # • lockfile = TOMLFile(self.lock)
@@ -317,6 +315,7 @@ def _write_lock_data(self, data: TOMLDocument) -> None:
                 f.write(content)
 
         else:
+            lockfile = TOMLFile(self.lock)
             lockfile.write(data)
 
         self._lock_data = None