Credit Suisse, Switzerland's second-largest bank, has been affected by a major leak of over 18,000 accounts opened between the 1940s and the 2010s, exposing alleged fraudsters and sanctioned individuals. The European People's Party (EPP) has called for a review of the EU's relationship with Switzerland, its fourth economic partner.

On his account, Chief economist at Tressis Gestion, Daniel Lacalle, said that "the logical steps would be to conduct a thorough investigation, find responsibilities, and put in place measures to ensure nothing similar happens again."

He added that "I believe that the days of lack of transparency are gone and Credit Suisse will likely strengthen its procedures to implement full compliance with the rules," stressing that "this news is ultimately positive because they make banks strengthen their compliance and transparency processes.”

According to Sergio Rossi, professor of macroeconomics and monetary economics at the University of Fribourg in Switzerland, German banks, as well as UK and US banks, may benefit from Credit Suisse's weakness.

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They could "recover either German wealthy clients or several other Western high-net-worth individuals, who might be very disappointed by the recent scandals that have been affecting Credit Suisse and its reputation", the academic added.

"It could accelerate the process towards the dissolution of Credit Suisse as a global player, since it seems now that it is very unlikely for Credit Suisse to re-establish its own reputation and credibility in the fields of asset and wealth management across the globe in the next couple of years", Rossi concluded.

Credit Suisse denied the charges, saying they are "predominantly historical" and that "the accounts of these matters are based on partial, inaccurate, or selective information taken out of context, resulting in tendentious interpretations of the bank's business conduct", Euronews reported.

The bank detailed that about 90% of accounts listed in the leak "are today closed or were in the process of closure prior to receipt of the press inquiries, of which over 60% were closed before 2015."

The leak 

A data leak from Credit Suisse exposed details of more than 30,000 accounts according to a German newspaper and other media outlets on Sunday, pointing to apparent failures of due diligence in checks on many customers.

The newspaper said it analyzed the data alongside the OCCRP (Organized Crime and Corruption Reporting Project) and dozens of media partners, including The New York Times and The Guardian, from the 1940s until well into the last decade.

According to the report, the bank has accepted customers who are "corrupt autocrats, suspected war criminals, and human traffickers, drug dealers, and other criminals."

A human trafficker convicted in the Philippines, a Hong Kong stock exchange chairman imprisoned for bribery, and an Egyptian billionaire who ordered the assassination of his Lebanese pop star girlfriend are among those exposed.

A former Siemens manager was listed as having six accounts after being convicted of bribery in 2008.

One of the former Siemens executives' accounts had assets worth more than 54 million Swiss francs (about $58.54 million) in 2006, according to the publication, which cannot be attributed to his Siemens income.

The revelation also discloses the hidden accounts of Jordan's King Abdullah II, Iraq's former Deputy Prime Minister Ayad Allawi, Algerian ex-President Abdelaziz Bouteflika, and Armenia's ex-President Armen Sarkissian.