Such obligations generally include disclosing proper anti-money laundering controls and abiding by regulatory demands.

Banque Havilland has disputed the ECB decision and said it would lodge an appeal.

Sources close to the Rowland family have also voiced their discontent. “The actions of the ECB are unjust, politically motivated and unnecessary and will not be left unchallenged,” said one source.

Banque Havilland was founded as a bank for the super rich, boasting branches in Liechtenstein, Switzerland, Dubai and Monaco.

But as the bank grew in stature, financial watchdogs became increasingly concerned about its strident activities on the global stage.

The Financial Conduct Authority (FCA), Britain’s financial watchdog, last year took action over claims the lender had plotted to manipulate Qatar’s currency amid a broader dispute in the Middle East in 2017.

Edmund Rowland, the chief executive of Havilland’s now closed London office and Rowland’s son, as well as two other employees, were subsequently banned by the regulator over their role in the alleged plot and the bank was fined £10 million ($19.4 million).

According to the FCA allegations, Edmund Rowland and the two employees hatched a plan for the United Arab Emirates to wage a financial war against Qatar by manipulating the bond market to attack the country’s currency.

The allegations underscored Banque Havilland’s deep ties to the UAE. Abu Dhabi’s crown prince and ruler, Mohammed bin Zayed, known as MbZ, was a major Havilland client and known as “the boss” at the bank, according to reports by Bloomberg.

The Qatar bond manipulation plan was “a way of marketing its services” to some of its wealthy clients in the UAE, the FCA said.

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The proposal was allegedly sent to Abu Dhabi’s sovereign wealth fund, known as Mubadala, and William Tricks, a former MI6 station chief in Abu Dhabi who worked as a contractor for Banque Havilland and had ties to MbZ.

Banque Havilland and Edmund Rowland dispute the FCA’s findings and are appealing the decision.

However, the troubles did not stop there.

In 2018, the bank was slapped with a major fine closer to home by Luxembourg’s financial regulator, the Commission de Surveillance du Secteur Financier (CSSF), over anti-money laundering failures.

The CSSF, led by grizzled regulator Claude Marx, said the lender failed to comply with rules on “sound and prudent business management” and the “fight against money laundering”.

Banque Havilland was forced to set up a “remediation plan” and report back to the regulator.

For David Rowland, the swirl of controversy around his bank is the latest setback for the businessman.

The embattled 79-year-old, who has eight children, has for years been pilloried for his cut-throat approach to business and cosy ties to the Duke.

The son of a scrap metal dealer from South London, he became a millionaire during the Swinging Sixties after bursting on to the property investment trust scene.

Owing to his youthful appearance and teenage acne, the City nicknamed him “Spotty”, a name that has stuck ever since.

Later in life, he became friends with the Duke and edged further into political circles.

After a stint as a significant Tory donor, he later sought to ascend to the role of Conservative Party treasurer.

However, he stood down shortly after his appointment in 2010 amid scrutiny of his tax affairs. Prior to that, he had been a long-term tax exile in Guernsey before returning to the UK.

The Tory treasurer bust-up prompted closer scrutiny of Rowland’s business affairs, and raised questions about the close ties between the Duke’s role as former international trade envoy and Banque Havilland’s bid to lure wealthy clients.

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Described in some reports as an “unofficial door-opener” for Rowland and Banque Havilland, the Duke’s globe-trotting role offered a useful way to win new clients.

The relationship also led to Mr Rowland paying off a £1.5 million loan taken out by the Duke with Banque Havilland, Bloomberg reported.

Although Rowland owns the bank, he has held no formal role in it. A number of family members, including his sons Jonathan and Edmund, have held directorships or senior positions in the past.

Harley Rowland, a 44-year-old former millennium hedge fund manager, is currently the family’s representative on the board.

Following the ECB’s move, Banque Havilland has stopped taking deposits and payments and the CSSF has been forced to step in to wind down the bank in orderly fashion.

Around 200 staff who work in Luxembourg are likely to lose their jobs although they remain in post awaiting more information.

Havilland’s branches in Liechtenstein and Switzerland have also been placed into voluntary liquidation ahead of the ECB’s decision.

The only survivor of the Havilland empire is likely to be its branch in Monaco, with the 20-person office set to be sold to a buyer before the end of the month, according to a source familiar with the matter.

Banque Havilland declined to comment and referred to a prior statement. Rowland could not be reached for comment. The ECB declined to comment.

The Telegraph, London

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