Italy’s UniCredit moved to buy another big chunk of Commerzbank, shrugging off German opposition to a possible takeover and upping the ante in its attempt to create a European banking champion with nearly $1.

UniCredit SpA Chief Executive Officer Andrea Orcel used Barclays Plc to help quietly build up a stake in Commerzbank AG, a move that has shaken European finance and triggered a backlash from the German government.

Italian bank says purchase will complete only once it receives regulatory approval to increase holding from 9%