Dutch bank ABN AMRO can proceed with its sale of U.S. unit LaSalle, the Dutch Supreme Court said, boosting the prospect Barclays will succeed in its near $90 billion takeover bid for ABN.

The ruling will force a consortium led by Royal Bank of Scotland which is also seeking to buy ABN to rethink its strategy, and is likely to see it revise its offer to exclude LaSalle as part of a deal, ahead of a deadline in 10 days.

A takeover of ABN would be the biggest ever bank deal.

The Supreme Court ruled on Friday that shareholders would not have to vote on the $21 billion sale of LaSalle to Bank of America (BofA), in line with advice given by a court adviser two weeks ago.

(The) request for an interim injunction to suspend ... the contract of sale regarding LaSalle was dismissed irrevocably, the court told a packed courtroom during a 20 minute ruling in The Hague.

After dramatically accelerating the usual court process, a judge said any new case brought before a Dutch court to stop the LaSalle sale has little chance of success.

Barclays has agreed an all-share offer for ABN worth about 64 billion euros ($88.2 billion).

A consortium of RBS, Fortis and Santander has trumped that with a mostly cash offer for ABN worth 71 billion euros, but only if LaSalle remained part of the bank. The consortium aimed to split up ABN's assets among the partners.

Analysts expect the consortium to revise its offer for ABN to exclude LaSalle.

We think it is very likely that the RBS-led consortium comes back with an offer ex-LaSalle, which was only 15 percent of the consortium synergies, Bruce Packard, analyst at Pali International, said after the court decision.

ABN shares were 0.7 percent higher at 35.55 euros by 0950 GMT. Shares in Barclays added 0.6 percent, while Santander and Fortis rose almost 1 percent and RBS was little changed.

Dutch shareholder group VEB, which represents small investors and which brought the original suit against ABN, said it now expects the sale of LaSalle to BofA to go through. But it said VEB will continue a separate case over the conduct of ABN's management in selling the bank.

The Supreme Court said the commercial court still had to decide on a request to set up an inquiry into policy and conduct of ABN's management.

Barclays welcomed what it said was a very clear ruling. The ruling is definite and therefore removes uncertainty from the situation, which is good for ABN AMRO customers and employees, John Varley, Barclays chief executive, said.

Fortis and Santander said they were evaluating the ruling within the consortium and would make a statement later. RBS, which has led the trio's offer, declined to comment.

A source close to the consortium told Reuters on Thursday it planned to revise its offer and bid for ABN without LaSalle if the court ruling went against it,

Barclays and the consortium have until July 23 to submit their offers.

A spokesman for BofA said it is satisfied with the ruling and will now continue with its purchase.

(Additional reporting by Steve Slater and Clara Ferreira-Marques in London and Niclas Mika and Harro ten Wolde in Amsterdam.)