Italian banking giant UniCredit has launched a formal takeover bid for German lender Commerzbank, marking the latest development in its extended campaign to acquire the Frankfurt-based bank.

The offer is valued at approximately $28-35 billion, with UniCredit seeking to increase its stake in Commerzbank to 30 percent as part of the acquisition strategy. The Italian bank already holds a position in Commerzbank and is now moving to strengthen its ownership significantly.

The bid represents UniCredit's renewed effort to revive takeover discussions with the German financial institution. Previous attempts by the Italian bank to engage Commerzbank in merger talks have faced various challenges, making this formal offer a notable escalation in the acquisition process.

Commerzbank is one of Germany's major commercial banks and has been the subject of consolidation speculation in the European banking sector. The potential takeover would create one of Europe's largest banking groups if successful.

The transaction would need regulatory approval from both Italian and German financial authorities, as well as acceptance from Commerzbank's management and shareholders. Cross-border banking mergers in Europe often face scrutiny from regulators concerned about market concentration and financial stability.