But to start with, London-based financial regulation expert David Heffron told me what e-money and stablecoin actually are.

E-money is electronically stored monetary value that represents a claim on the issuer.

So it's essentially a prepaid value.

The customer gives money to the issuer, it receives e-money in return, and then uses it for payments or other transactions.

The important distinction is it's not a deposit.

And why is that important? It's important because e-money doesn't benefit from what we would know as FSCS protection, so that's Financial Services Compensation Scheme protection.

And it's analogous to regulated stablecoins, which are also emerging as another form of digital money.

So what is the PRA's solution to stopping the contagion? Clearer separation of e-money and traditional money, says David.