API to call for deactivating accounts

Hi all:

Using the API, is there a way to activate/deactivate the user account?

What we need to do is: 

1. Deactivate the user account
2. Wait 90 days (In this time if the account needs to be reactivated we need to be able to)
3. Delete the deactivated account

We are planning on calling this process through an ASP.NET web service.