The likely collapse of Barclays’ €67.5 billion (£47 billion) bid for ABN Amro this week will cost the British bank £80 million in fees paid to advisers.

But the biggest losers, if ABN does reject Barclays, as most analysts expect, will be the six investment banks advising on the deal. Banking sources believe that the advisers stand to lose at least £400 million and possibly as much as £800 million in fees.

BarCap, Citigroup, Credit Suisse, JPMorgan Cazenove, Deutsche Bank and Lazards are understood to have been retained by Barclays on the basis that the majority of their fees will be paid only if the bid is successful.

If the deal fails, these investment banks will also lose out in the City’s all-important mergers and acquisitions league tables for this year.

Barclays is thought to have deliberately sought as wide a group of advisers as possible in order to limit the expertise available to its rival for ABN, a consortium led by Royal Bank of Scotland. The RBS consortium is advised by Merrill Lynch, which could earn up to €600 million from a successful bid.

ABN shareholders will decide on Thursday whether to accept the Barclays bid or the €71.1 billion offer from the RBS consortium.

John Varley, the chief executive of Barclays, has been adamant that he will not raise his offer because it would contravene strict financial tests that the company sets for acquisitions.

The bank has said that its current offer would pass its tests on return on investment versus cost of capital and economic profit within three years. A higher offer would “bomb” the tests, banking sources said. As a result, ABN’s shareholders are expected to opt for the RBS consortium’s higher-cash bid.

Barclays’ executives will now start preparing for a shareholder roadshow as they attempt to explain why losing the race for ABN has not damaged their plans for international growth.

The bank is also expected to launch an internal programme to ensure that its own staff understand the outcome of the takeover battle.

The bank’s strategy has been to seek faster growth by internationalising its earnings base. It is expected to argue that, although acquiring ABN would have helped to speed up this process, Barclays is capable of achieving the same result from organic growth, albeit at a slower pace.

The bank will also be able to tell investors that a failed bid for ABN will allow it to turn a profit. Its estimated £80 million costs will be offset by the €250 million it will receive from ABN as part of a break fee arranged when they were in exclusive negotiations earlier this year. There will be no such consolation for the six investment banks acting as advisers to Barclays.

There is still a slim possibility that the RBS-led consortium will fail in its attempt to win ABN. European regulators will decide on Wednesday whether plans by Fortis, which is part of the consortium, for its share of ABN contravene competition rules.

Fortis, a Belgian bank, is proposing to take over the Dutch assets of ABN and has agreed to sell Hollandsche Bank Unie, 13 advisory offices and two corporate client units on completion of the deal. This should allow the European Commission to wave through Fortis’s plans when the regulators meet on Wednesday.

Royal Bank of Scotland had by last Friday successfully raised €6 billion to fund its share of the consortium’s bid. Fortis is currently on a roadshow for its €13 billion rights issue, which is also required to fund the consortium’s offer. The third member of the consortium is Banco Santander of Spain.

ABN is expected to spend several hundred million euros on advisers’ fees after six months of negotiations with Barclays and the RBS consortium. It is being advised by Morgan Stanley, Lehman Brothers, UBS and Rothschild.

ABN and Barclays entered exclusive negotiations in March but a month later RBS contacted the Dutch bank to indicate its own interest. The ABN board withdrew its recommendation of the Barclays bid in July.

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