If someone calls and asks, “Can you hear me?”, hang up the phone immediately.

A major phone scam from the US is set to cross the pond and hit the UK imminently.

But police and call-blocking companies are warning the public about the dangerous phone call in the hope of preventing innocent people falling victim to the scammers.

Here’s how it works:

You receive a phone call from a local number

The voice on the end introduces themselves and the company they supposedly work for

They then ask: “Can you hear me?”

Your answer is recorded, and if you say “yes”, your response will be edited to make it appear as if you’ve agreed to a huge purchase.

You’re effectively being tricked into signing a verbal contract, much the same as clicking ‘I agree’ to terms and conditions online.

Voice signatures like these are legitimately used by companies doing business over the phone, but this is being exploited by scammers who have conned many Americans already, predominantly in Florida, Pennsylvania and Virginia.

CPR Call Blocker has seen the scam rise in frequency and the company believes it’s only a matter of time before Brits start being targeted too, according to the Sunderland Echo.

“In our experience of working across the US and UK, scams spread quickly across the pond,” says Kris Hicks from CPR Call Blocker. He adds that it’s sensible for Brits to be on their guard “as we have no doubt that fraudsters operating in the UK will soon start using these tactics.”

The scammers may try and charge you for products or services you’ve never used, and if you try and argue with them, they’ll play back their recording of you saying “yes” and threaten to take legal action if you don’t pay up.

Another version of the scam sees the criminals using the person’s voice recording to authorise a stolen credit card.

The public is being advised either to hang up straight away upon being asked “Can you hear me?”, or just not pick up at all if you don’t recognise the number.