MySQL Workbench: How to detach reverse-engineered EER diagram from existing database?

MySQL Workbench provides the option to 'Create EER Model From Existing Database'. Trying to remove a table from the resulting diagram leads to a dialog asking:

Should corresponding database objects be deleted with the figures?

As the database must be left untouched in any case, my question is now: How to safely detach the EER model / diagram from the underlying database?