Access XML_ID of pageItem/groupItem

Is it possible to access the XML_ID of  a pageItem or groupItem via ExtendScript?

For example a layer name may be 'Active' but it's XML_ID (as viewed when setting Preferences > Identify Object By > XML ID) may be 'Active_1_' due to a copy and paste operation.

So the Object name would be groupItem.name  but there is no groupItem.id or groupItem.xml_id for example?

Does anyone know a way to access these?

Many thanks,

Michael