(Bloomberg) -- Four bankers including the former boss of Gazprombank’s Swiss unit were convicted for failing in their due diligence requirements to properly flag financial transactions made by a cello-playing confidant of Vladimir Putin. 

The men were handed suspended sentences subject to two years of probation, a Zurich district court said in a statement on Thursday. The ex-head of Gazprombank Schweiz AG was fined 540,000 Swiss francs ($590,000), while two senior executives and a client relationship manager were ordered to pay lesser amounts. 

They had all been on trial for negligence of their handling between 2014 and 2016 of finances linked to Sergei Roldugin — described by the U.S. Treasury as “a custodian of Putin’s offshore wealth.”

Roldugin is a “close friend” of the Russian president and godfather to Putin’s daughter, and the bankers should’ve scrutinized if he was the real beneficial owner of Gazprombank accounts belonging to shell companies in Panama and Cyprus, the prosecutors argued.

Set against the backdrop of Putin’s invasion of Ukraine and Switzerland’s role as a hub of Russian money, the trial was widely seen as a test of local prosecutors’ willingness and ability to punish what they believe to be financial wrongdoing amid a war that has upended traditional Swiss neutrality. 

The four men, who cannot be named under Swiss court reporting restrictions, all had denied wrongdoing during the trial. All four announced after their sentencing that they will appeal the verdict, a spokesman for the bank said. 

Foreign critics have argued that Switzerland doesn’t do enough to crackdown on financial crime domestically or on illicit Russian money there. Swiss authorities have frozen about 7.5 billion Swiss francs ($8.2 billion) as part of sanctions efforts, compared to at least 150 billion francs in Russian assets stashed in the country, according to the Swiss Bankers’ Association.

Roldugin was among those in Putin’s circle that the European Union sanctioned over a year ago after the invasion of Ukraine. He was seen as a conduit of the vast fortune Western governments say Putin accumulated over his nearly quarter-century in power. 

The Kremlin has previously acknowledged that Putin is a friend of Roldugin, who recognizes the work he has done for Russian music, but denies any financial improprieties.

Gazprombank Schweiz still has its banking license but is currently in the process of winding down which it began last year following Russian’s invasion of Ukraine.

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