doc/install.rst | 5 +++--
 doc/news.rst    | 8 ++++++++
 pyderasn.py     | 6 ++++--

diff --git a/doc/install.rst b/doc/install.rst
index d5f01c01b6c22a3d352801b37ce70e364c2df540f2f51bd4e2c24fafea296ec2..657fc4fe01b21337b01f322b4719151f68088a5c84361b671cdfc9dc5952af7d 100644
--- a/doc/install.rst
+++ b/doc/install.rst
@@ -12,8 +12,9 @@     $ cd pyderasn-9.0
     $ python setup.py install
     # or copy pyderasn.py (possibly termcolor.py) to your PYTHONPATH
 
-``termcolor`` is an optional dependency used for output colourizing.
-``urwid`` is an optional dependency used for :ref:`interactive browser <browser>`.
+* ``termcolor`` is an optional dependency used for output colourizing.
+* ``urwid`` is an optional dependency used for :ref:`interactive browser <browser>`.
+* ``dateutil`` is an optional dependency used for ``.totzdatetime()`` method.
 
 You could use pip (**no** OpenPGP authentication is performed!) with PyPI::
 
diff --git a/doc/news.rst b/doc/news.rst
index 5e3612cfedee1190f563d4f6a72a0c2b0c9174667b5e1f1ff691e3ec00ed16b4..2e95b4cd6ca8543818dce1005a4b0cc30f1f71d8479ac66569202111b6a4f2eb 100644
--- a/doc/news.rst
+++ b/doc/news.rst
@@ -1,6 +1,14 @@
 News
 ====
 
+.. _release9.1:
+
+9.1
+---
+* ``.totzdatetime()`` appeared in UTCTime and GeneralizedTime,
+  explicitly setting UTC timezone information.
+  Optional ``dateutils.tz`` library is required for that
+
 .. _release9.0:
 
 9.0
diff --git a/pyderasn.py b/pyderasn.py
index 6d39433e8786f3cec82565e8a0c09b4ea0741e6ed17eff393afedd83488731ad..0b9199c2b044c6aac1f654c57ffff9533159d21be451128e15ee5f36c9f2ed47 100755
--- a/pyderasn.py
+++ b/pyderasn.py
@@ -971,12 +971,12 @@
 UTCTime
 _______
 .. autoclass:: pyderasn.UTCTime
-   :members: __init__, todatetime
+   :members: __init__, todatetime, totzdatetime
 
 GeneralizedTime
 _______________
 .. autoclass:: pyderasn.GeneralizedTime
-   :members: __init__, todatetime
+   :members: __init__, todatetime, totzdatetime
 
 Special types
 -------------
@@ -5038,6 +5038,8 @@     >>> t.todatetime()
     datetime.datetime(2017, 9, 30, 22, 7, 50)
     >>> UTCTime(datetime(2057, 9, 30, 22, 7, 50)).todatetime()
     datetime.datetime(1957, 9, 30, 22, 7, 50)
+    >>> UTCTime(datetime(2057, 9, 30, 22, 7, 50)).totzdatetime()
+    datetime.datetime(1957, 9, 30, 22, 7, 50, tzinfo=tzutc())
 
     If BER encoded value was met, then ``ber_raw`` attribute will hold
     its raw representation.