diff --git a/climateclient/v1/leases.py b/climateclient/v1/leases.py
index a509a19..54c6f01 100644
--- a/climateclient/v1/leases.py
+++ b/climateclient/v1/leases.py
@@ -36,19 +36,22 @@ class LeaseClientManager(base.BaseClientManager):
         """
         return self._get('/leases/%s' % lease_id, 'lease')
 
-    def update(self, lease_id, name=None, prolong_for=None):
+    def update(self, lease_id, name=None, prolong_for=None, reduce_by=None):
         """Update attributes of the lease."""
         values = {}
         if name:
             values['name'] = name
-        if prolong_for:
-            if prolong_for.endswith('s'):
+
+        lease_length_option = prolong_for or reduce_by
+
+        if lease_length_option:
+            if lease_length_option.endswith('s'):
                 coefficient = 1
-            elif prolong_for.endswith('m'):
+            elif lease_length_option.endswith('m'):
                 coefficient = 60
-            elif prolong_for.endswith('h'):
+            elif lease_length_option.endswith('h'):
                 coefficient = 60 * 60
-            elif prolong_for.endswith('d'):
+            elif lease_length_option.endswith('d'):
                 coefficient = 24 * 60 * 60
             else:
                 raise exception.ClimateClientException(_("Unsupportable date "
@@ -57,7 +60,8 @@ class LeaseClientManager(base.BaseClientManager):
             lease = self.get(lease_id)
             cur_end_date = datetime.datetime.strptime(lease['end_date'],
                                                       '%Y-%m-%dT%H:%M:%S.%f')
-            seconds = int(prolong_for[:-1]) * coefficient
+            coefficient = coefficient * (1 if prolong_for else -1)
+            seconds = int(lease_length_option[:-1]) * coefficient
             delta_sec = datetime.timedelta(seconds=seconds)
             new_end_date = cur_end_date + delta_sec
             values['end_date'] = datetime.datetime.strftime(
diff --git a/climateclient/v1/shell_commands/leases.py b/climateclient/v1/shell_commands/leases.py
index d82a246..81d02e2 100644
--- a/climateclient/v1/shell_commands/leases.py
+++ b/climateclient/v1/shell_commands/leases.py
@@ -220,16 +220,23 @@ class UpdateLease(command.UpdateCommand):
             help='New name for the lease',
             default=None
         )
-        parser.add_argument(
+        #prolong-for and reduce_by are mutually exclusive
+        group = parser.add_mutually_exclusive_group()
+        group.add_argument(
             '--prolong-for',
             help='Time to prolong lease for',
             default=None
         )
-        parser.add_argument(
+        group.add_argument(
             '--prolong_for',
             help=argparse.SUPPRESS,
             default=None
         )
+        group.add_argument(
+            '--reduce-by',
+            help='Time to reduce lease by',
+            default=None
+        )
         return parser
 
     def args2body(self, parsed_args):
@@ -238,6 +245,8 @@ class UpdateLease(command.UpdateCommand):
             params['name'] = parsed_args.name
         if parsed_args.prolong_for:
             params['prolong_for'] = parsed_args.prolong_for
+        if parsed_args.reduce_by:
+            params['reduce_by'] = parsed_args.reduce_by
         return params