The consortium led by UK banking giant Royal Bank of Scotland (RBS) that is considering a counter bid to rival Barclays' £46 billion ($111.5 billion) merger with ABN Amro has cancelled talks with the Dutch bank.

RBS and Spanish bank Banco Santander cancelled talks with ABN Amro after it was revealed that ABN Amro planned to sell its United States subsidiary LaSalle Bank to Bank of America for US$21 billion ($25.5 billion).

The consortium, which also includes Belgium-based Fortis Bank, said that its takeover plans involved the retention of LaSalle Bank and a meeting with ABN Amro would now be inappropriate.

"In view of ABN Amro's decision to sell LaSalle Bank to Bank of America, the banks need to understand the circumstances under which this sale can be terminated. The banks are requesting this information today," the consortium said in a statement to the London Stock Exchange on Monday.

The decision by ABN Amro to sell LaSalle bank and insert a termination fee of US$200 million payable to Bank of America, if the agreement is terminated under certain limited circumstances, has widely been viewed as a poison pill to put RBS off.

"We are concerned the pre-agreed sale of LaSalle Bank unfairly hinders the RBS consortium," United Kingdom hedge fund TCI was reported as saying earlier this week.

Barclays is offering 3.225 of its own shares for each ABN Amro share, which values them at €36.25 each.