diff --git a/airflow/api/auth/backend/session.py b/airflow/api/auth/backend/session.py
index d51f7bf1cf4c9..e6b4da691213e 100644
--- a/airflow/api/auth/backend/session.py
+++ b/airflow/api/auth/backend/session.py
@@ -18,30 +18,21 @@
 
 from __future__ import annotations
 
-from functools import wraps
-from typing import Any, Callable, TypeVar, cast
+import warnings
+from typing import Any
 
-from flask import Response
-
-from airflow.www.extensions.init_auth_manager import get_auth_manager
+import airflow.providers.fab.auth_manager.api.auth.backend.session as fab_session
+from airflow.exceptions import RemovedInAirflow3Warning
 
 CLIENT_AUTH: tuple[str, str] | Any | None = None
 
 
-def init_app(_):
-    """Initialize authentication backend."""
-
-
-T = TypeVar("T", bound=Callable)
-
-
-def requires_authentication(function: T):
-    """Decorate functions that require authentication."""
+warnings.warn(
+    "This module is deprecated. Please use `airflow.providers.fab.auth_manager.api.auth.backend.session` instead.",
+    RemovedInAirflow3Warning,
+    stacklevel=2,
+)
 
-    @wraps(function)
-    def decorated(*args, **kwargs):
-        if not get_auth_manager().is_logged_in():
-            return Response("Unauthorized", 401, {})
-        return function(*args, **kwargs)
 
-    return cast(T, decorated)
+init_app = fab_session.init_app
+requires_authentication = fab_session.requires_authentication
diff --git a/providers/tests/fab/auth_manager/api_endpoints/test_auth.py b/providers/tests/fab/auth_manager/api_endpoints/test_auth.py
index 630ce7050bed5..2a0463e510abf 100644
--- a/providers/tests/fab/auth_manager/api_endpoints/test_auth.py
+++ b/providers/tests/fab/auth_manager/api_endpoints/test_auth.py
@@ -148,7 +148,7 @@ def with_basic_auth_backend(self, minimal_app_for_auth_api):
                     (
                         "api",
                         "auth_backends",
-                    ): "airflow.api.auth.backend.session,airflow.providers.fab.auth_manager.api.auth.backend.basic_auth"
+                    ): "airflow.providers.fab.auth_manager.api.auth.backend.session,airflow.providers.fab.auth_manager.api.auth.backend.basic_auth"
                 }
             ):
                 init_api_auth(minimal_app_for_auth_api)
diff --git a/providers/tests/fab/auth_manager/conftest.py b/providers/tests/fab/auth_manager/conftest.py
index 9102f5d0f65d4..88fd34977df59 100644
--- a/providers/tests/fab/auth_manager/conftest.py
+++ b/providers/tests/fab/auth_manager/conftest.py
@@ -43,7 +43,7 @@ def factory():
                 (
                     "api",
                     "auth_backends",
-                ): "providers.tests.fab.auth_manager.api_endpoints.remote_user_api_auth_backend,airflow.api.auth.backend.session",
+                ): "providers.tests.fab.auth_manager.api_endpoints.remote_user_api_auth_backend,airflow.providers.fab.auth_manager.api.auth.backend.session",
                 (
                     "core",
                     "auth_manager",
diff --git a/tests/api_connexion/test_auth.py b/tests/api_connexion/test_auth.py
index e568d618ad662..e3b70922d5fae 100644
--- a/tests/api_connexion/test_auth.py
+++ b/tests/api_connexion/test_auth.py
@@ -44,7 +44,9 @@ def with_session_backend(self, minimal_app_for_api):
         old_auth = getattr(minimal_app_for_api, "api_auth")
 
         try:
-            with conf_vars({("api", "auth_backends"): "airflow.api.auth.backend.session"}):
+            with conf_vars(
+                {("api", "auth_backends"): "airflow.providers.fab.auth_manager.api.auth.backend.session"}
+            ):
                 init_api_auth(minimal_app_for_api)
                 yield
         finally: