diff --git a/tryton/gui/window/view_form/view/form_gtk/float.py b/tryton/gui/window/view_form/view/form_gtk/float.py
index 4d4d9d808e..442a8cfcce 100644
--- a/tryton/gui/window/view_form/view/form_gtk/float.py
+++ b/tryton/gui/window/view_form/view/form_gtk/float.py
@@ -30,6 +30,8 @@ class Float(Integer):
         position = entry.get_position()
         new_value = value[:position] + new_text + value[position:]
         try:
+            if new_value == '-':
+                return
             if len(str(int(locale.atof(new_value)))) > self.digits[0]:
                 entry.stop_emission('insert-text')
         except:
diff --git a/tryton/gui/window/view_form/view/form_gtk/integer.py b/tryton/gui/window/view_form/view/form_gtk/integer.py
index 32fbd1e8fb..9b17039df1 100644
--- a/tryton/gui/window/view_form/view/form_gtk/integer.py
+++ b/tryton/gui/window/view_form/view/form_gtk/integer.py
@@ -31,6 +31,8 @@ class Integer(Char):
         position = entry.get_position()
         new_value = value[:position] + new_text + value[position:]
         try:
+            if new_value == '-':
+                return
             locale.atoi(new_value)
         except:
             entry.stop_emission('insert-text')