Royal Bank of Scotland was left fuming after a last-minute maneouvre by ABN Amro threatened to dash its hopes of mounting a break-up bid for the Dutch lender, which Monday agreed a €66bn takeover by Barclays.

Sir Fred Goodwin, chief executive of RBS, was understood to be furious after ABN Amro confirmed on Monday that it was selling LaSalle, its US banking operation, to Bank of America for $21bn in cash. The sale, which does not need to be approved by shareholders, may undermine a planned break-up of ABN Amro by RBS, Santander of Spain and Fortis, the Belgo-Dutch banking and insurance group.