Martin Lewis warns Brits can now be charged £6 daily for using a phone in some places during the holidays

Money Saving Expert Martin Lewis has warned millions of Brits could be stung with a daily £6 charge if they're not careful. The finance journalist issued a warning to people after rules changed.

Thanks to Brexit, Brits visiting EU countries will no longer be immune to roaming charges on some networks. Mobile firms were previously banned from charging extra fees to use your UK allowance - calls, texts and data - while holidaying in the EU.

But because of Brexit, mobile providers are now able to charge people for using their phones abroad, and if you're not careful, it could prove very costly. EE describes a day use in the EU as anything up to 11.59pm UK time, the same day. So if you sign up at 11.58pm, you would only get a minute's worth of data for your money.

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Vodafone charges £2 which lasts 24 hours from first use in the EU - but in the rest of the world, it charges £6 for roaming and this ends at 11.59pm in the capital of the country being visited.

Three customers are charged £2 a “day” which is also 24 hours from first use. The network provider also offers £5 a “day” data passport for unlimited data in the UK and 89 destinations - but only up to 11.59pm UK time.

Some smaller piggyback networks have introduced charges too, says the Mirror. Virgin Media O2 is the only network giant still offering roaming at no extra cost - although it has changed its “fair use” policy, which is separate to roaming fees. “Fair use” caps the amount of your UK data allowance you can use for free while roaming in Europe.

Mobile firms were allowed to set “fair use” caps before Brexit. Martin Lewis, founder of MoneySavingExpert, said: "I've no faith in