Cellist Sergei Roldugin receives a medal from Vladimir Putin in September 2016 (Photo: AP)

Four bankers have been convicted of managing the bank accounts of a friend of Vladimir Putin.

The unnamed workers, three Russian-born and one Swiss, were employed by Gazprombank Switzerland.

Cellist Sergei Roldugin was a client of the bank between 2014 and 2016. There were suspicions about his activities in the 2016 Panama Papers leaks.

Prosecutors accused Putin’s friend Roldugin of helping smuggle millions abroad and said finance officials could turn a blind eye to such flows.

The US Treasury Department describes him as “part of a system that manages President Putin’s foreign assets”.

His income was listed in the bank as CHF 1 million per annum (£886,000) and his net worth at CHF 10 million (£8.8 million).

However, his profession as a musician is on record, indicating that the cash flows “are in no way plausible as Roldugin’s net worth,” according to the indictment.

The musician estimated his income at one million Swiss francs a year (£886,000) (Photo: Getty)

In addition, Gazprombank maintained Roldugin’s accounts despite “numerous” media reports of his relationship with Putin, including that he was godfather to one of the president’s daughters.

Roldugin is one of many people who have faced sanctions from Western countries because of their close ties to Putin’s government.

The four bankers involved in this case were accused of providing insufficient evidence that Mr. Roldugin owned the accounts and that they had violated Swiss money laundering law.

They all denied the charges against them, but were sentenced on 8 March after a court hearing.

They were sentenced to seven months’ probation by the Zurich court.

Violations of these penalties can lead to fines totaling hundreds of thousands of francs.

The lawyers for all suspects immediately announced an appeal.

The district prosecutor’s office in Zurich welcomes the rulings in a statement as “an important signal that due diligence for money laundering must be adhered to”.

Gazprombank Switzerland, a Zurich-based channel of the Russian bank on the brink of bankruptcy, has not been charged as an organization.

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