diff --git a/trytond/doc/topics/views/index.rst b/trytond/doc/topics/views/index.rst
index 41f879cc23..fa3f3d0846 100644
--- a/trytond/doc/topics/views/index.rst
+++ b/trytond/doc/topics/views/index.rst
@@ -752,7 +752,10 @@ displayed in the same column with the attributes:
 button
 ------
 
-Same as form-button_.
+Same as form-button_ with the addition of:
+
+``width``
+   The width of the column.
 
 List-Form
 =========
diff --git a/trytond/trytond/ir/ui/tree.rnc b/trytond/trytond/ir/ui/tree.rnc
index 07a7308d9b..9024f9ba56 100644
--- a/trytond/trytond/ir/ui/tree.rnc
+++ b/trytond/trytond/ir/ui/tree.rnc
@@ -96,6 +96,7 @@ attlist.button &= attribute change { text }?
 attlist.button &= attribute type { "class" | "instance" }?
 attlist.button &=
   [ a:defaultValue = "0" ] attribute tree_invisible { text }?
+attlist.button &= attribute width { text }?
 data = element data { attlist.data, xpath* }
 attlist.data &= empty
 xpath = element xpath { attlist.xpath,
diff --git a/trytond/trytond/ir/ui/tree.rng b/trytond/trytond/ir/ui/tree.rng
index 36356d0814..96be5760a1 100644
--- a/trytond/trytond/ir/ui/tree.rng
+++ b/trytond/trytond/ir/ui/tree.rng
@@ -487,6 +487,14 @@
       </attribute>
     </optional>
   </define>
+  <define name="attlist.button" combine="interleave">
+    <optional>
+      <attribute>
+        <name ns="">width</name>
+        <text/>
+      </attribute>
+    </optional>
+  </define>
   <define name="data">
     <element>
       <name ns="">data</name>