The following charts show how the two banks differ across an array of measures and what any combined bank could look like: 1. UNICREDIT VS. COMMERZBANK The Italian lender is more efficient and more profitable than its German counterpart - with a market capitalisation that is more than triple the value of Commerzbank.

The drivers of recent banking transactions are many of those that have shaped the European banking industry for the past 15 years: sluggish revenue outlook as the sugar rush of higher interest rates fades and rising costs as the promise of IT-driven efficiency is continually offset by higher investment spend,

ECB chief Christine Lagarde said Monday that cross-border banking mergers in Europe were "desirable" to boost their competitiveness, despite mounting German opposition to a potential tie-up between Commerzbank and Italy's UniCredit.