diff --git a/securesystemslib/interface.py b/securesystemslib/interface.py
index 44e0a6e1..dbce936d 100755
--- a/securesystemslib/interface.py
+++ b/securesystemslib/interface.py
@@ -173,7 +173,7 @@ def _get_key_file_decryption_password(password, prompt, path):
 
 
 
-def generate_and_write_rsa_keypair(filepath=None, bits=DEFAULT_RSA_KEY_BITS,
+def _generate_and_write_rsa_keypair(filepath=None, bits=DEFAULT_RSA_KEY_BITS,
     password=None, prompt=False):
   """Generates RSA key pair and writes PEM-encoded keys to disk.
 
@@ -341,7 +341,7 @@ def import_rsa_publickey_from_file(filepath, scheme='rsassa-pss-sha256',
 
 
 
-def generate_and_write_ed25519_keypair(filepath=None, password=None,
+def _generate_and_write_ed25519_keypair(filepath=None, password=None,
     prompt=False):
   """Generates ed25519 key pair and writes custom JSON-formatted keys to disk.
 
@@ -496,7 +496,7 @@ def import_ed25519_privatekey_from_file(filepath, password=None, prompt=False,
 
 
 
-def generate_and_write_ecdsa_keypair(filepath=None, password=None,
+def _generate_and_write_ecdsa_keypair(filepath=None, password=None,
     prompt=False):
   """Generates ecdsa key pair and writes custom JSON-formatted keys to disk.
 
diff --git a/tests/check_public_interfaces.py b/tests/check_public_interfaces.py
index dcec9c00..5005c707 100644
--- a/tests/check_public_interfaces.py
+++ b/tests/check_public_interfaces.py
@@ -64,7 +64,7 @@ def test_interface(self):
 
     with self.assertRaises(
           securesystemslib.exceptions.UnsupportedLibraryError):
-      securesystemslib.interface.generate_and_write_rsa_keypair(password='pw')
+      securesystemslib.interface._generate_and_write_rsa_keypair(password='pw')
 
     with self.assertRaises(
           securesystemslib.exceptions.UnsupportedLibraryError):
@@ -75,7 +75,7 @@ def test_interface(self):
 
     with self.assertRaises(
           securesystemslib.exceptions.UnsupportedLibraryError):
-      securesystemslib.interface.generate_and_write_ed25519_keypair(
+      securesystemslib.interface._generate_and_write_ed25519_keypair(
           password='pw')
 
     with self.assertRaises(
@@ -88,7 +88,7 @@ def test_interface(self):
 
     with self.assertRaises(
           securesystemslib.exceptions.UnsupportedLibraryError):
-      securesystemslib.interface.generate_and_write_ecdsa_keypair(
+      securesystemslib.interface._generate_and_write_ecdsa_keypair(
           password='pw')
 
     with self.assertRaises(
diff --git a/tests/test_interface.py b/tests/test_interface.py
index 49adfd6f..334775bd 100755
--- a/tests/test_interface.py
+++ b/tests/test_interface.py
@@ -60,13 +60,13 @@
 from securesystemslib.exceptions import Error, FormatError, CryptoError
 
 from securesystemslib.interface import (
-    generate_and_write_rsa_keypair,
+    _generate_and_write_rsa_keypair,
     import_rsa_privatekey_from_file,
     import_rsa_publickey_from_file,
-    generate_and_write_ed25519_keypair,
+    _generate_and_write_ed25519_keypair,
     import_ed25519_publickey_from_file,
     import_ed25519_privatekey_from_file,
-    generate_and_write_ecdsa_keypair,
+    _generate_and_write_ecdsa_keypair,
     import_ecdsa_publickey_from_file,
     import_ecdsa_privatekey_from_file,
     import_publickeys_from_file,
@@ -101,12 +101,12 @@ def tearDown(self):
 
 
   def test_rsa(self):
-    """Test RSA key generation and import interface functions. """
+    """Test RSA key _generation and import interface functions. """
 
     # TEST: Generate default keys and import
     # Assert location and format
     fn_default = "default"
-    fn_default_ret = generate_and_write_rsa_keypair(filepath=fn_default)
+    fn_default_ret = _generate_and_write_rsa_keypair(filepath=fn_default)
 
     pub = import_rsa_publickey_from_file(fn_default + ".pub")
     priv = import_rsa_privatekey_from_file(fn_default)
@@ -123,13 +123,13 @@ def test_rsa(self):
     # Assert importable without password
     fn_empty_prompt = "empty_prompt"
     with mock.patch("securesystemslib.interface.get_password", return_value=""):
-      generate_and_write_rsa_keypair(filepath=fn_empty_prompt, prompt=True)
+      _generate_and_write_rsa_keypair(filepath=fn_empty_prompt, prompt=True)
     import_rsa_privatekey_from_file(fn_empty_prompt)
 
 
     # TEST: Generate keys with auto-filename, i.e. keyid
     # Assert filename is keyid
-    fn_keyid = generate_and_write_rsa_keypair()
+    fn_keyid = _generate_and_write_rsa_keypair()
     pub = import_rsa_publickey_from_file(fn_keyid + ".pub")
     priv = import_rsa_privatekey_from_file(fn_keyid)
     self.assertTrue(
@@ -140,7 +140,7 @@ def test_rsa(self):
     # Assert length
     bits = 4096
     fn_bits = "bits"
-    generate_and_write_rsa_keypair(filepath=fn_bits, bits=bits)
+    _generate_and_write_rsa_keypair(filepath=fn_bits, bits=bits)
 
     priv = import_rsa_privatekey_from_file(fn_bits)
     # NOTE: Parse PEM with pyca/cryptography to get the key size property
@@ -158,10 +158,10 @@ def test_rsa(self):
     fn_prompt = "prompt"
 
     # ... a passed pw ...
-    generate_and_write_rsa_keypair(filepath=fn_encrypted, password=pw)
+    _generate_and_write_rsa_keypair(filepath=fn_encrypted, password=pw)
     with mock.patch("securesystemslib.interface.get_password", return_value=pw):
       # ... and a prompted pw.
-      generate_and_write_rsa_keypair(filepath=fn_prompt, prompt=True)
+      _generate_and_write_rsa_keypair(filepath=fn_prompt, prompt=True)
 
       # Assert that both private keys are importable using the prompted pw ...
       import_rsa_privatekey_from_file(fn_prompt, prompt=True)
@@ -194,7 +194,7 @@ def test_rsa(self):
           "passing 'password' and 'prompt=True' is not allowed")]):
 
       with self.assertRaises(ValueError, msg="(row {})".format(idx)) as ctx:
-        generate_and_write_rsa_keypair(**kwargs)
+        _generate_and_write_rsa_keypair(**kwargs)
 
       self.assertEqual(err_msg, str(ctx.exception),
           "expected: '{}' got: '{}' (row {})".format(
@@ -208,7 +208,7 @@ def test_rsa(self):
         {"password": 123456}, # Not a string
         {"prompt": "not-a-bool"}]):
       with self.assertRaises(FormatError, msg="(row {})".format(idx)):
-        generate_and_write_rsa_keypair(**kwargs)
+        _generate_and_write_rsa_keypair(**kwargs)
 
 
     # TEST: Import errors
@@ -280,12 +280,12 @@ def test_rsa(self):
 
 
   def test_ed25519(self):
-    """Test ed25519 key generation and import interface functions. """
+    """Test ed25519 key _generation and import interface functions. """
 
     # TEST: Generate default keys and import
     # Assert location and format
     fn_default = "default"
-    fn_default_ret = generate_and_write_ed25519_keypair(filepath=fn_default)
+    fn_default_ret = _generate_and_write_ed25519_keypair(filepath=fn_default)
 
     pub = import_ed25519_publickey_from_file(fn_default + ".pub")
     priv = import_ed25519_privatekey_from_file(fn_default)
@@ -302,14 +302,14 @@ def test_ed25519(self):
     # Assert importable with empty prompt password and without password
     fn_empty_prompt = "empty_prompt"
     with mock.patch("securesystemslib.interface.get_password", return_value=""):
-      generate_and_write_ed25519_keypair(filepath=fn_empty_prompt)
+      _generate_and_write_ed25519_keypair(filepath=fn_empty_prompt)
       import_ed25519_privatekey_from_file(fn_empty_prompt, prompt=True)
     import_ed25519_privatekey_from_file(fn_empty_prompt)
 
 
     # TEST: Generate keys with auto-filename, i.e. keyid
     # Assert filename is keyid
-    fn_keyid = generate_and_write_ed25519_keypair()
+    fn_keyid = _generate_and_write_ed25519_keypair()
     pub = import_ed25519_publickey_from_file(fn_keyid + ".pub")
     priv = import_ed25519_privatekey_from_file(fn_keyid)
     self.assertTrue(
@@ -321,10 +321,10 @@ def test_ed25519(self):
     fn_encrypted = "encrypted"
     fn_prompt = "prompt"
     # ... a passed pw ...
-    generate_and_write_ed25519_keypair(filepath=fn_encrypted, password=pw)
+    _generate_and_write_ed25519_keypair(filepath=fn_encrypted, password=pw)
     with mock.patch("securesystemslib.interface.get_password", return_value=pw):
       # ... and a prompted pw.
-      generate_and_write_ed25519_keypair(filepath=fn_prompt, prompt=True)
+      _generate_and_write_ed25519_keypair(filepath=fn_prompt, prompt=True)
 
       # Assert that both private keys are importable using the prompted pw ...
       import_ed25519_privatekey_from_file(fn_prompt, prompt=True)
@@ -370,7 +370,7 @@ def test_ed25519(self):
           "passing 'password' and 'prompt=True' is not allowed")]):
 
       with self.assertRaises(ValueError, msg="(row {})".format(idx)) as ctx:
-        generate_and_write_ed25519_keypair(**kwargs)
+        _generate_and_write_ed25519_keypair(**kwargs)
 
       self.assertEqual(err_msg, str(ctx.exception),
           "expected: '{}' got: '{}' (row {})".format(
@@ -382,7 +382,7 @@ def test_ed25519(self):
         {"password": 123456}, # Not a string
         {"prompt": "not-a-bool"}]):
       with self.assertRaises(FormatError, msg="(row {})".format(idx)):
-        generate_and_write_ed25519_keypair(**kwargs)
+        _generate_and_write_ed25519_keypair(**kwargs)
 
 
     # TEST: Import errors
@@ -459,11 +459,11 @@ def test_ed25519(self):
 
 
   def test_ecdsa(self):
-    """Test ecdsa key generation and import interface functions. """
+    """Test ecdsa key _generation and import interface functions. """
     # TEST: Generate default keys and import
     # Assert location and format
     fn_default = "default"
-    fn_default_ret = generate_and_write_ecdsa_keypair(filepath=fn_default)
+    fn_default_ret = _generate_and_write_ecdsa_keypair(filepath=fn_default)
 
     pub = import_ecdsa_publickey_from_file(fn_default + ".pub")
     priv = import_ecdsa_privatekey_from_file(fn_default)
@@ -479,14 +479,14 @@ def test_ecdsa(self):
     # Assert importable with empty prompt password and without password
     fn_empty_prompt = "empty_prompt"
     with mock.patch("securesystemslib.interface.get_password", return_value=""):
-      generate_and_write_ecdsa_keypair(filepath=fn_empty_prompt)
+      _generate_and_write_ecdsa_keypair(filepath=fn_empty_prompt)
       import_ecdsa_privatekey_from_file(fn_empty_prompt, prompt=True)
     import_ecdsa_privatekey_from_file(fn_empty_prompt)
 
 
     # TEST: Generate keys with auto-filename, i.e. keyid
     # Assert filename is keyid
-    fn_keyid = generate_and_write_ecdsa_keypair()
+    fn_keyid = _generate_and_write_ecdsa_keypair()
     pub = import_ecdsa_publickey_from_file(fn_keyid + ".pub")
     priv = import_ecdsa_privatekey_from_file(fn_keyid)
     self.assertTrue(
@@ -498,10 +498,10 @@ def test_ecdsa(self):
     fn_encrypted = "encrypted"
     fn_prompt = "prompt"
     # ...  a passed pw ...
-    generate_and_write_ecdsa_keypair(filepath=fn_encrypted, password=pw)
+    _generate_and_write_ecdsa_keypair(filepath=fn_encrypted, password=pw)
     with mock.patch("securesystemslib.interface.get_password", return_value=pw):
       # ... and a prompted pw.
-      generate_and_write_ecdsa_keypair(filepath=fn_prompt, prompt=True)
+      _generate_and_write_ecdsa_keypair(filepath=fn_prompt, prompt=True)
 
       # Assert that both private keys are importable using the prompted pw ...
       import_ecdsa_privatekey_from_file(fn_prompt, prompt=True)
@@ -540,7 +540,7 @@ def test_ecdsa(self):
           "passing 'password' and 'prompt=True' is not allowed")]):
 
       with self.assertRaises(ValueError, msg="(row {})".format(idx)) as ctx:
-        generate_and_write_ecdsa_keypair(**kwargs)
+        _generate_and_write_ecdsa_keypair(**kwargs)
 
       self.assertEqual(err_msg, str(ctx.exception),
           "expected: '{}' got: '{}' (row {})".format(
@@ -552,7 +552,7 @@ def test_ecdsa(self):
         {"password": 123456}, # Not a string
         {"prompt": "not-a-bool"}]):
       with self.assertRaises(FormatError, msg="(row {})".format(idx)):
-        generate_and_write_ecdsa_keypair(**kwargs)
+        _generate_and_write_ecdsa_keypair(**kwargs)
 
 
     # TEST: Import errors