diff --git a/changelogs/fragments/70168-fix-delegate_facts-without-interpreter-set.yml b/changelogs/fragments/70168-fix-delegate_facts-without-interpreter-set.yml
new file mode 100644
index 00000000000..371778eabb2
--- /dev/null
+++ b/changelogs/fragments/70168-fix-delegate_facts-without-interpreter-set.yml
@@ -0,0 +1,2 @@
+bugfixes:
+  - "Fix ``delegate_facts: true`` when ``ansible_python_interpreter`` is not set. (https://github.com/ansible/ansible/issues/70168)"
diff --git a/lib/ansible/plugins/action/__init__.py b/lib/ansible/plugins/action/__init__.py
index 83c7715d3ee..565b27502cd 100644
--- a/lib/ansible/plugins/action/__init__.py
+++ b/lib/ansible/plugins/action/__init__.py
@@ -160,7 +160,7 @@ class ActionBase(with_metaclass(ABCMeta, object)):
         '''
 
         if task_vars is None:
-            use_vars = dict()
+            task_vars = {}
 
         if self._task.delegate_to:
             use_vars = task_vars.get('ansible_delegated_vars')[self._task.delegate_to]
@@ -248,15 +248,16 @@ class ActionBase(with_metaclass(ABCMeta, object)):
                 if not self._task.delegate_to or self._task.delegate_facts:
                     # store in local task_vars facts collection for the retry and any other usages in this worker
                     if use_vars.get('ansible_facts') is None:
-                        task_vars['ansible_facts'] = {}
-                    task_vars['ansible_facts'][discovered_key] = self._discovered_interpreter
+                        task_vars['ansible_facts'] = use_vars['ansible_facts'] = {}
+                    task_vars['ansible_facts'][discovered_key] = use_vars['ansible_facts'][discovered_key] = self._discovered_interpreter
                     # preserve this so _execute_module can propagate back to controller as a fact
                     self._discovered_interpreter_key = discovered_key
                 else:
-                    task_vars['ansible_delegated_vars'][self._task.delegate_to]
                     if task_vars['ansible_delegated_vars'][self._task.delegate_to].get('ansible_facts') is None:
                         task_vars['ansible_delegated_vars'][self._task.delegate_to]['ansible_facts'] = {}
+                        use_vars['ansible_delegated_vars'][self._task.delegate_to]['ansible_facts'] = {}
                     task_vars['ansible_delegated_vars'][self._task.delegate_to]['ansible_facts'][discovered_key] = self._discovered_interpreter
+                    use_vars['ansible_delegated_vars'][self._task.delegate_to]['ansible_facts'][discovered_key] = self._discovered_interpreter
 
         return (module_style, module_shebang, module_data, module_path)
 
diff --git a/test/integration/targets/delegate_to/aliases b/test/integration/targets/delegate_to/aliases
index b8e973dacea..5ba9106d8ad 100644
--- a/test/integration/targets/delegate_to/aliases
+++ b/test/integration/targets/delegate_to/aliases
@@ -2,3 +2,4 @@ shippable/posix/group3
 needs/ssh
 needs/root  # only on macOS and FreeBSD to configure network interfaces
 skip/aix
+non_local # workaround to allow override of ansible_python_interpreter; disables coverage on this integration target
diff --git a/test/integration/targets/delegate_to/runme.sh b/test/integration/targets/delegate_to/runme.sh
index 8095c921d23..b315d20ef84 100755
--- a/test/integration/targets/delegate_to/runme.sh
+++ b/test/integration/targets/delegate_to/runme.sh
@@ -70,3 +70,6 @@ ln -s python secondpython
 )
 ansible-playbook verify_interpreter.yml -i inventory_interpreters -v "$@"
 ansible-playbook discovery_applied.yml -i inventory -v "$@"
+
+# https://github.com/ansible/ansible/issues/70168
+ansible-playbook verify_interpreter_delegate_facts.yml -i inventory -v "$@"
diff --git a/test/integration/targets/delegate_to/verify_interpreter_delegate_facts.yml b/test/integration/targets/delegate_to/verify_interpreter_delegate_facts.yml
new file mode 100644
index 00000000000..27e90ed49c8
--- /dev/null
+++ b/test/integration/targets/delegate_to/verify_interpreter_delegate_facts.yml
@@ -0,0 +1,11 @@
+- hosts: testhost
+  gather_facts: yes
+  tasks:
+    - detect_interpreter:
+      delegate_to: "{{ item }}"
+      delegate_facts: yes
+      vars:
+        ansible_python_interpreter: auto
+      loop:
+        - testhost3
+        - testhost4