diff --git a/pamac-daemon.py b/pamac-daemon.py
index 3a4fb0b..1c89e0f 100755
--- a/pamac-daemon.py
+++ b/pamac-daemon.py
@@ -521,11 +521,11 @@ class PamacDBusService(dbus.service.Object):
 		finally:
 			return error
 
-	@dbus.service.method('org.manjaro.pamac', '', 's')
-	def Sysupgrade(self):
+	@dbus.service.method('org.manjaro.pamac', 'b', 's')
+	def Sysupgrade(self, downgrade):
 		error = ''
 		try:
-			self.t.sysupgrade(downgrade=False)
+			self.t.sysupgrade(downgrade = bool(downgrade))
 		except pyalpm.error as e:
 			error = format_error(e.args)
 			self.t.release()
diff --git a/pamac/transaction.py b/pamac/transaction.py
index e6900b5..5e513ed 100644
--- a/pamac/transaction.py
+++ b/pamac/transaction.py
@@ -786,7 +786,7 @@ def set_transaction_sum(show_updates = True):
 	else:
 		sum_bottom_label.set_markup('<b>{} {}</b>'.format(_('Total download size:'), common.format_size(dsize)))
 
-def sysupgrade(show_updates = True):
+def sysupgrade(show_updates = True, downgrade = False):
 	syncfirst, updates = available_updates
 	if updates:
 		global to_update
@@ -834,7 +834,7 @@ def sysupgrade(show_updates = True):
 				error += init_transaction()
 				if not error:
 					if to_update:
-						error += Sysupgrade()
+						error += Sysupgrade(downgrade)
 					_error = ''
 					for name in to_add:
 						_error += Add(name)