Germany’s chancellor decried “unfriendly attacks” on banks after UniCredit moved to raise its stake in the lender.

Italian government officials are growing frustrated at Germany’s opposition to a potential takeover of Commerzbank AG by Milan-based UniCredit Spa, threatening to disrupt the delicate diplomatic relations between Berlin and Rome.

UniCredit is "doing well" to act within the European Union's internal market, Italian Foreign Minister Antonio Tajani told the Class CNBC network on Monday, commenting on the Milan-based bank interest for Germany's Commerzbank .