Barclays plans to sweeten its offer for ABN Amro with more cash after the rival RBS-led consortium on Monday revised its offer for the Dutch bank.

But even as Barclays was preparing its counter-punch, it faced investor calls to walk away. The RBS consortium, which includes Belgo-Dutch bank Fortis and Santander of Spain, tabled a new €71.1bn (£48.1bn) bid for ABN and raised the cash proportion from 79 to 93 per cent.