The chief executive of Hypo Landesbank Vorarlberg, an Austrian lender mentioned in the massive "Panama Papers" data leak, has become one of the first top bankers to quit over reports based on those files.

Michael Grahammer, who has been chief executive since 2012, has told the bank he is stepping down, the lender said on Thursday, adding his decision was a surprise.

Austrian broadcaster ORF, one of the more than 100 news organisations that investigated the trove of data leaked from a Panama-based law firm, said the bank was connected to offshore companies through trustees in Liechtenstein.

Austrian financial markets regulator FMA is investigating whether Hypo Vorarlberg and another Austrian bank mentioned in the Panama Papers reports, Raiffeisen Bank International, took steps required to prevent money laundering.

“I remain 100 per cent convinced that the bank at no point violated laws or sanctions,” Mr Grahammer said in a statement issued by the bank, majority-owned by the province of Vorarlberg, which borders Liechtenstein and Switzerland.

The decision was the result of various developments in the past year, he said, adding:

“In the end, the media’s prejudgement of Hypo Vorarlberg and of myself in recent days was decisive for me in taking this step.”

Reuters