A UK driving licence is valid if you drive in the EU both for work and as a visitor. When the UK leaves the EU on March 29th 2019 – if there is no deal – then your driving licence will no longer be valid for use in EU countries. You will  need other accompanying documents. This includes if you wish to hire a vehicle.
https://theorkneynews.scot/2018/11/02/how-to-prepare-if-the-uk-leaves-the-eu-with-no-deal-driving/