Disable user creation in IdentityManager (web)

Hi guys,

I'm searching for an easy solution to disable the user creation in the Web IdentityManager, in case that we don't want to allow users these option.
It would be also fine if we just can disable the button in the web-interface, unfortunately I don't found any solution here how to fix this on a easy way. Also if there is an option just to remove the permission.

I'm talking about "My Direct Reports" > "Explore" > "Add a new identity".

Thanks for your input!