The Swiss authorities have reportedly frozen three bank accounts of the former head of private Greek bank Proton.
Greek businessman Lavrentis Lavrentiadis is under investigation by Greek prosecutors for alleged fraud, embezzlement and corruption involving up to 700 million euros.
Lavrentiadis vigorously denies the allegations and has accused the authorities of acting illegally.
A Swiss banking source confirmed earlier Swiss and German newspaper reports that the Greek authorities had requested the blocking of accounts holding up to 160 million euros.
A spokeswoman at the Swiss Department of Justice and Police of Switzerland said: “We do not comment in principle on a provisional remedy in connection with criminal proceedings”.
An audit by the Bank of Greece, which regulates the financial industry, found that more than 40 percent of Proton’s commercial loans in 2010 were made to companies related to Lavrentiadis. The report says this was part of a “misuse of the basic principles of lending and assurance”.
A separate investigation, signed by a senior prosecutor who heads the country’s money laundering authority, found that Lavrentiadis had with others “formed a criminal team” that embezzled up to 51 million euros from the bank.
It alleged loans made to dormant companies had been wired from Proton to another bank, the Piraeus Bank, and then withdrawn by an employee in bags of cash.
Lavrentiadis, once hailed as the rising star of Greek business and known as a leading patron of the arts, was named “Greek Entrepreneur of the Year” in 2007.
The Proton bank was bailed out by the Greek state in October.