Horta-Osorio left Credit Suisse in January after only nine months following an internal probe into his personal conduct, including breaches of COVID-19 rules.

His role at Mediobanca will be to support the implementation of its strategy, working with the co-heads of Corporate & Investment Banking, Francisco Bachiller and Giuseppe Baldelli, on expanding client relationships and deal activity across Europe, the bank said in a statement.

"I have known Antonio for many years, and I have always been impressed by his unique experience and distinguished track record in senior executive roles," said Alberto Nagel, Chief Executive Officer of Mediobanca.

Horta-Osorio was also chief executive of Britain's Lloyds Banking Group for a decade until 2021.

(Writing by Keith Weir, Editing by Louise Heavens)