diff --git a/src/poetry/core/packages/project_package.py b/src/poetry/core/packages/project_package.py
index 046c8da28..fab0792f0 100644
--- a/src/poetry/core/packages/project_package.py
+++ b/src/poetry/core/packages/project_package.py
@@ -1,5 +1,6 @@
 from __future__ import annotations
 
+import logging
 import warnings
 
 from typing import TYPE_CHECKING
@@ -17,6 +18,9 @@
 from poetry.core.packages.utils.utils import create_nested_marker
 
 
+logger = logging.getLogger(__name__)
+
+
 class ProjectPackage(Package):
     def __init__(
         self,
@@ -34,6 +38,15 @@ def __init__(
 
         super().__init__(name, version)
 
+        if name != self.name and "." in name:
+            logger.warning(
+                f"Project name has been canonicalised from <info>{name}</info> to"
+                f" <info>{self.name}</info>. This may not be compatible with previous"
+                " releases or package metadata looks and may cause issues when"
+                " uploading to package repositories. See"
+                " https://github.com/python-poetry/poetry/issues/6198.",
+            )
+
         self.build_config: dict[str, Any] = {}
         self.packages: list[dict[str, Any]] = []
         self.include: list[dict[str, Any]] = []