Rogue trader Nick Leeson has claimed authorities in Ireland and Britain do not have the appetite to prosecute bankers.

Twenty years since his spectacularly fraudulent punts broke Barings, one of the UK’s oldest merchant banks, the former derivatives broker hit out at apathy he sees among criminal justice chiefs and politicians.

“The problem is there needs to be an appetite to prosecute these people,” he said. “There seems to be a severe lack of appetite when you look at the UK and Ireland and you have to ask yourself why?

“Financial markets are a huge part of a country’s GDP, they provide a lot of donations to the ruling parties in both those countries and there just seems to be a lack of appetite to prosecute and punish accordingly.”

Leeson’s staggering fraud from the Singapore trading floor still resonates two decades later, albeit the £862m losses he racked up are dwarfed by the multibillion bailouts of UK and Irish banks and fines of $166bn dished out to banks for corrupt or illegal practices in recent years.

But the plasterer’s son from Watford remains a symbol of rogue banking.

Leeson appeared incredulous at the lack of white-collar convictions for corrupt banking and more so at the apparently pervasive attitudes in financial circles.

“There’s been some startling things that have happened over the last number of years and when you sort of add them together it kind of looks as if they [the banks] exist above the law,” he said.

“166 billion US dollars in fines in six years is astronomical sort of money. If you can weather that sort of fine, number one, and it doesn’t impact your bottom line and there’s no reputational damage — what stops you carrying on and working forward to the next disaster that’s around the corner because there’s no real consequence to your actions.”

Leeson, who this week turns 48, has been jailed, divorced, beaten colon cancer, run Galway United Football Club, and carved a lucrative career on the after dinner circuit and as a debt management consultant in the years since Barings collapsed on February 26 1995.

The venerable investment house counted Queen Elizabeth on its client list and is mentioned in history books as the institution that financed the sale of the state of Louisiana from France.

Ultimately it was sold for £1 and Leeson’s reckless trades were depicted in a Hollywood film starring Ewan McGregor.

Now re-married, Leeson’s turnaround is evidenced by the comfortable, suburban life he has built with his second wife Leona in Galway.

Even that took an unusual twist last week when he used the Barings’ anniversary as an opportunity to explain to his 10-year-old son Mackensey why his father will be in the news again.

Monday marked the 20th anniversary since he fled the “police state” of Singapore, as he puts it, with his first wife Lisa and hid in a Malaysian hotel. A fax had been sent to his London bosses claiming he was sick and wanted to resign.

Three days later he was preparing to hand himself in and Barings was bust.

Leeson went on to serve four and a half years in a Singapore prison for fraud and illegal trading, going through divorce while behind bars before being released early to battle colon cancer.

Leeson’s life has enjoyed a remarkable turnaround, but he does not see a similar trajectory in the world of banking.

“It’s all about money. But wherever it is, in society, we have rules and laws and they’re enforced.

“The problem with the world of banking for me at the moment is there isn’t adequate deterrent and meaningful punishment and if you have a lack of the two there’ll be bedlam, people will do what they want.”