Restricting client access to other Office 365 tenants

Hi,

   When allowing connectivity into Office 365, is there a way to restrict access to a single a tenant? For the purposes of DLP I need to prevent internal machines logging onto any another email service including other 365 tenants, how could this be acheived? 

Google offer a way to restrict this by using additional headers -> https://support.google.com/a/answer/1668854?hl=en

Many thanks,

-Ben