But today's successful court challenge from Dutch shareholder group VEB, which claimed the La Salle deal was an attempt to block other parties from bidding for ABN, has resulted in the freezing of the forthcoming Barclays sale.
Now the likelihood of a successful bid from a rival group emerges as a possibility. A consortium of three banks headed by the Royal Bank of Scotland (RBS) has also expressed its intention of putting forward an offer for the group on the condition that the US unit is not sold.
RBS, along with Spain's Santander and the Belgian-Dutch bank Fortis, is expected to make an unsolicited offer for ABN following the Barclays sale collapse.
Commentators say such a move would place ABN under the potential threat of legal action from Barclays, which could sue the Dutch group if it subsequently reneges on its takeover agreement with the British bank.
ABN could also face action from the Bank of America in the LaSalle deal does not come to fruition, while reports suggest that the RBS-led consortium could launch a lawsuit to try and block the sell-off if the Dutch court does ratify the sale.
"The accelerated side deal to sell LaSalle has created a non-comparable situation for shareholders, may deter the highest offer and opens a legal minefield," said Keefe, Bruyette & Woods analyst Jean-Pierre Lambert in a note.
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