Iceland boss reveals how shoplifters handed 'carte blanche to steal' in 'war on UK high streets'

He has now urged the Government and other retailers to treat Britain's shoplifting epidemic more seriously.

"Shoplifting sounds like cheeky pilfering, but actually it should be called violent crime because we're talking about thieves using knives, needles and hammers in threats to our staff," Mr Walker told the Financial Times's Future of Retail conference.

He blasted the current law, which sees thieves who steal goods equating to less than £200 in value spared from prison, as giving a "carte blanche to shoplifters".

As such, Mr Walker welcomed recent moves to toughen laws against shoplifters, including legislation to remove the £200 threshold.

Earlier this year, Iceland introduced a controversial facial recognition trial which detects shoplifters and directly sends their profile to police databases.

However, Mr Walker said his supermarket had been slapped down by the UK's data watchdog, the Information Commissioner's Office - which said displaying images of prolific shoplifters would impact their human rights.

He blasted this as "idiotic", saying: "I've advised shop managers to do it because this is a low-level war going on every day across our high streets and we need to take it very seriously."

Campaigners branded Iceland's implementation of facial recognition as "chilling".

The Big Brother Watch group said on social media: "Thousands of people will have their privacy rights violated just to buy basic necessities, and Iceland will turn its shoppers into suspects, making them submit to a biometric identity check as part of their daily lives."

In another bid to crack down on shoplifters, Mr Walker revealed a scheme in August which would see a reward for shoppers who reported thieves.

He said: "I would like to announce we will give £1 to any customer who points out a shoplifter. If they see any customer in our stores who are undertaking that offence and tell our colleagues and it turns out they are, we will put it straight on their bonus card. Done."

However, social media users criticised the scheme - and called the reward amount insulting.

Shoplifting in the UK has reached a record high this year.

According to the Office for National Statistics, there were 530,643 shoplifting offences reported in the year to March, a 20 per cent increase on the year before.

Not only are the number of offences increasing, but the rate of incarceration is falling.

Almost six in 10 chronic thieves - those with at least 15 previous convictions - avoided jail last year.

This is the highest rate since Ministry of Justice records began more than a decade ago.