IDPs are already needed if you plan to drive in many countries outside the EU/EEA.
You only need an IDP if you are definitely going to travel abroad.
If the UK leaves the EU without a deal IDPs may also be required to drive in EU/EEA countries.
There are three different types of IDP in use. You may need more than one IDP depending on which countries you are visiting.
There is no requirement for UK licence holders visiting EU/EEA countries to undertake any additional test to drive after the UK leaves the EU.
IDPs cost £5.50 and can be obtained over the counter at 2,500 Post Offices around the UK.