The battle for control of Dutch banking group ABN Amro stepped up another gear this morning as Barclays formally launched its bid and gained European Commission clearance, while Fortis shareholders overwhelmingly backed the Belgo-Dutch bank's role in a rival Royal Bank of Scotland-led offer.

The RBS-led bid for ABN Amro received a boost after shareholders of Fortis voted to back its role in the deal at a meeting in Brussels. A second meeting in Utrecht this afternoon will determine the ultimate outcome of the vote.