When I associate a project with a client in CRM I don't want the Contacts to be added as users to the project

When I associate a project with a client in CRM I don't want the Contacts to be added as users to the project

When I associate a project with a client in CRM all of the contacts are made client users in the project. I don't want this to happen.  What do I need to do to remove the contacts from the project users?  We don't want clients to have access to any part of our projects at this time.

Thanks