Free data roaming across Europe for UK citizens is not a guarantee should the country fail to reach an agreement to leave the European Union (EU), a top government minister warned.

Speaking to BBC News, Brexit secretary Dominic Raab said there was no “cast iron guarantee” on the issue, and the government has said roaming could be offered with different terms and conditions in the event that the UK and the EU fail to reach an agreement.

For consumers, this could see the implementation of lower allowances for calls, text and data in Europe compared with the UK.

In theory, UK operators could reintroduce roaming charges across the EU, which were scrapped in June 2017, after the UK leaves the Union (scheduled to take place on 29 March 2019).

However, operators Vodafone UK, EE, O2 UK and 3 UK have pledged not to reintroduce additional surcharges to consumers travelling in Europe, after a deal has been reached and the UK leaves the EU.

A no-deal between the EU and the UK, however, complicates matters, as regulations on the amount European operators could charge UK operators would not apply. The UK government has said it will work to make sure operators set a cap of £45 a month on data usage abroad, in line with the €50 set by the EU.

The UK and EU are currently negotiating the wider terms of the country’s exit.

To read an analysis of what could happen with regards to roaming fees in the UK once the country leaves the EU, click here.