Brexit problems.

I am now not able to ship to Northern Ireland and need a way to exclude those postcodes from this shipping module.

To start with I just raised the shipping cost to those postcodes massively so people would not purchase, but that does not look good for my shops.

Is there a way to set one of the shipping zones to be a "No delivery" zone so if a customer tries to purchase using a postcode in that zone they get a message "Sorry but we are not able to ship to your address" message?