NatWest Group — formerly called RBS — said it is “increasing customer protection against crypto-criminals” after £329 million was lost by consumers last year.

NatWest said it is implementing a daily limit of £1,000 and a 30-day payment limit of £5,000 to cryptocurrency exchanges by the group’s customers “to help protect customers losing life changing sums of money.”

NatWest said: “Cryptocurrency investments are often made through legitimate exchange platforms.

“These websites let customers buy, sell or exchange cryptocurrencies for other digital currency or traditional currency.

“Men over 35 are most at risk due to them being more willing to take on risky investments. The cost-of-living crisis is also having an impact with promises of high returns used by criminals to entice investors.

“Cryptocurrency scams are often advertised online offering high returns on investments.

“Criminals play on a lack of understanding of how cryptocurrency markets work and their unpredictability, to encourage investors to transfer money to exchanges, which are often set up in the customer’s own name by the criminal or by the victim, under duress from the criminal.”

Stuart Skinner, Head of Fraud Protection NatWest, said: “You should always have sole control of your cryptocurrency wallet and nobody else should have access.

“If you didn’t set the wallet up yourself or can’t access the money then this is likely to be a scam.

“We have seen an increase in the number of scams using cryptocurrency exchanges and we are acting to protect our customers.”

NatWest said cryptocurrency is not protected by the UK’s Financial Services Compensation Scheme and most are not regulated by the Financial Conduct Authority.