Deutsche Bank has had the last laugh in the Interbrew fiasco after it emerged that the beer company's finance director Luc Missorten "abused" its analysts and accused it of "slagging off the offer".

Missorten was apparently peeved that Deutsche Bank wrote in a pre-flotation report that the company's £2.3bn deal to buy Bass's brewing business faced regulatory risks. And he dismissed the regulatory questions that were raised, according to a source at the bank.

As it turned out, Deutsche Bank was right to be concerned although a spokeswoman for Missorten insisted he did not play down the risks and that he had had a calm conversation with the bank to discuss how the firm was valuing the Belgian company.

Other investors and analysts who were at the initial public offering's road show claimed management routinely minimised or ignored the risk that the deal could get blocked although Interbrew said its prospects clearly detailed regulatory risks.

Now Interbrew faces the prospect of about a quarter of the £3.3bn raised in its flotation go out the window.

Investors will also say management lost credibility.