A consortium led by the Royal Bank of Scotland has put ABN Amro's wholesale banking business at the centre of its proposed takeover of the Dutch bank and sweetened the terms of its offer after losing out in a battle to acquire US retail unit LaSalle.

The UK bank, Fortis and Banco Santander boosted the cash element of their offer for ABN Amro by more than a tenth this morning but left the €38.40 a share offer unchanged. The indicative bid values ABN at €71.1bn ($98bn).