Britons could face limits on the amount of euros they can withdraw in the event of a no-deal Brexit, the Post Office has warned.

Travellers could face restrictions on purchases of European currency if Britain leaves the EU without a mutually-agreed plan.

The Post Office told HuffPost UK it had considered the possibility of a cap on bureaux transactions as part of its preparations for Brexit.

Andrew Brown, the firm’s foreign currency expert, said any imposed restriction would be unlikely to affect everyday travellers as most draw out only small amounts of notes and coins.

Brown also confirmed the Post Office has jetted in euros to build up its existing supplies ahead of Brexit day on 29 March.

“From a cash perspective, the only potential risk would be that restrictions are imposed at some point for the amount of Sterling or amount of Euros [travellers can buy],” Brown said.

“People would still be able to use their credit and debit cards – and they will still be able to use pre-paid cards – it would just potentially be a restriction on the amount of cash they could take,” he added.

“From a tourist perspective, I don’t think it will have any impact unless it was a really, really low restriction, and there’s no reason for that to happen.”

He said the average consumer spends around £800 on a holiday abroad, so they are “probably only taking £300 to £400 in cash”, which is a “relatively small amount”.

“We are planning for a worst-case scenario, we don’t know – it could all be like a Millennium bug – but we’re prepared,” he said. “We are making sure our supply lines are OK and that we have sufficient funds available to serve customers.”

Other currency firms, including Travelex and M&S Bank, said they regularly reviewed the market to provide consistent service to customers.

The Post Office said sales of euros were up 3% year-on-year in 2019 so far compared with January to mid-February in 2018.

The pound to Euro exchange rate traded at a near one-year high on Monday at £1.14.

Should I buy Euros now? Experts give their advice

Nathan Best, of Travelex, said it was “impossible to predict” how foreign currency exchange rates might change in future “especially with volatility around Brexit and other economic events.”

“The best customers can do is keep an eye on rates and convert at a rate they feel comfortable with.  One option for customers who are wary of foreign currency volatility is to split their currency purchases to reduce risk,” Best said.

Meanwhile, Andrew Brown said travellers preparing to go on holiday during or after 29 March should follow advice that applies regardless of Brexit – keep an eye on exchange rates and spread currency across cash and pre-paid cards.

“Don’t put all your money into cash and don’t rely solely on credit cards. The main thing is to keep an eye on the exchange rates,” he said.

“If it is going up, or down, it is up to the consumers whether they want to buy a small amount now or leave it.

“We see a variety of things, including people using the travel money pre-paid card to put £50 or so on every month, that way they have the Euros banked.”

HuffPost UK has approached the Treasury for comment.