After a 21-day scrutiny period in parliament and up to a year to pass enabling legislation, the convention requires the setting up of a new system for registration of trailers and the issuing of international driving permits (IDPs) if the EU refuses to recognise UK licences.

Insiders say the prospect of triggering this wave of extra red tape had led to furious rows within Whitehall but the lack of alternatives has forced proposed legislation – the haulage permits and trailer registration bill – to be rushed into the Lords.

 “There will be some costs in relation to the provision of a new system for issuing 1968 convention compliant IDPs, and the provision of a registration system for trailers travelling overseas,” said an accompanying government memo published on Wednesday.

Officials have insisted that it was not the government’s intention for UK drivers to need IDPs in Europe, but in an EU notice issued last month, the European commission said: “A driving licence issued by the United Kingdom will no longer be recognised by the member states.”

Without a recognised licence, travellers to Europe could find themselves unable to hire cars or take insurance, as has happened in some US states such as Florida, although some countries may choose not to enforce the convention.

The paper-based IDP can currently be obtained from a limited number of post offices as well as the AA and RAC for a charge of £5.50 and after tackling various bureaucratic hurdles.

“It’s extremely labour-intensive,” said AA spokesman, Ian Crowder. “It’s certainly a possibility that an IDP will be required in Europe, although we think it’s unlikely because we hope they will reach a deal.”

The Vienna convention requires drivers of certain trailers to seek a separate vehicle registration when travelling abroad. The government has said this will be mandatory for commercial drivers and larger non-commercial drivers, and voluntary for smaller caravans and horse boxes.