Mediobanca, the Italian investment bank, is considering its biggest move outside its domestic market by buying the German advisory business of Luxembourg-headquartered Sal Oppenheim, the private bank.

Mediobanca is carrying out due diligence on Sal Oppenheim’s German investment banking and equity capital markets business. It sees a possible purchase of the unit as a boost to its ambition to become a more active European investment banking group.

There have been some talks between Sal Oppenheim and Mediobanca on the matter. Sal Oppenheim is looking at another of options, a spokesperson for the firm told WealthBriefing.

Mediobanca’s interest in the German advisory business comes as Deutsche Bank carries out due diligence on taking a possible majority stake in Sal Oppenheim after making a non-binding offer. Deutsche Bank has one of Europe’s biggest investment banking franchises and is not interested in Sal Oppenheim’s investment banking operations, according to a report by the Financial Times.

Almost all of Mediobanca’s dealmaking firepower is concentrated in Milan, but it harbours ambitions to expand. It has opened offices in Paris, London, Madrid and Frankfurt in recent years, but they remain marginal to the overall business. The bank is understood to believe that adding investment bankers in Frankfurt would complement its position advising medium-sized companies.

In August, Deutsche Bank announced its intention to form a strategic partnership with Oppenheim, a private bank that traces its origins back more than 200 years. Deutsche has said it is optimistic that it will conclude negotiations to take a stake in Sal Oppenheim by mid-October - rebutting German media speculation that there was poor progress on the deal.

Deutsche Bank financed €300 million ($424 million) increase of Sal Oppenheim’s equity capital in mid-August.