British motorists may be required to have a green card while driving in the EU, insurance companies are told the government on Monday.
Drivers could be asked to obtain the document and carry it in EU member states after 31 December, even if a Brexit trade deal is agreed upon.
Insurance representatives informed the Transport Secretary through a direct message on Monday that those who do not observe the rules could be prosecuted and risk having their vehicle confiscated.
In the letter to Grant Shapps, ABI, a trade body that represents insurance firms, called on him to put further pressure on the European Commission to act and prevent the need for a green card.
"Insurers have put considerable resources into preparing for the need to issue green cards for travel from 1 January 2020 to minimise any disruption to motorists", said ABI’s assistant director Carol Hall.
Regarding the upcoming end of UK membership of the area where insurance certificates are not required, she said it is "without question that the best outcome for customers, road hauliers and insurers continues to be for the UK to be part of the green card free circulation zone".
"We appreciate the pragmatic approach the UK Government has taken on this matter, and we need them to press the EU Commission to agree that the UK and its motorists can stay in the green card free zone", she added.
Without intervention from the EC, even motorists in Northern Ireland who drive south into the Republic of Ireland would require the insurance pass.
The document functions as an international certificate provided by insurers as proof that foreign motorists meet the minimum requirements of compulsory motor insurance cover. However, they have not been a necessity for Brits prior to the UK's withdrawal from the EU.
All European Economic Area (EEA) countries - which includes all EU member states, as well as Iceland, Liechtenstein, and Norway - are included as the Green Card free circulation area. This means motorists from those regions do not require Green Cards when visiting other countries also in the area.
However, once the Brexit transition period ends, UK motorists will automatically be required to possess Green Cards while driving in Republic and other EU countries, unless the European Commission permits Britain to stay as part of the arrangement.
Unless the Commission permits continued membership of the free circulation zone, once the transition period closes at the end of the year, motorists using their vehicles in the EU will need to carry the permit.