The merger has left a bitter taste in the mouth of many investors

The new company will have a global market share of 14% and will be the world's second biggest brewer behind Budweiser firm Anheuser-Busch.

Brazil offers Interbrew a market with an increasing thirst for beer at a time when European drinkers are drying up.

But Interbrew shares fell, on concern growth was at the expense of wringing more profit from existing brands.

Dominant

Some analysts have said that Interbrew is paying over the odds for the company and accused it of going back on a pledge to consolidate previous acquisitions.

TOP BREWERS BY TURNOVER Anheuser-Busch InterbrewAmbev SABMiller Heineken Carlsberg

The company's stock fell more than 5% in Brussels and many observers said it was unlikely to recover soon.

Chief executive John Brock was more upbeat, however, predicting that the merger would enhance profitability and prospects.

According to his calculations the merger will result in cost savings of 280m euros (�186m; $340m) a year from 2006.

The combined company would control about 14% of the world's beer market.

Interbrew said it would look to use AmBev's dominant local position - it has about 65% of the Brazilian market - and region-wide distribution network to introduce products in Latin America.

INTERBREW BRANDS Stella Artois Beck's Bass Leffe Staropramen Hoegaarden

For Interbrew, the deal "represents an opportunity to enter some of the fastest growing beer markets in the world," said Mr Brock.

AmBev's chairman Marcel Herrmann Telles said it meant the company's management "can now achieve our long-term goal of opening the world's largest markets for AmBev's brands".

Share swaps

While the plan may be simple enough, the agreement between the two companies is complex, involving share swaps as well as cash.

Interbrew is set to pay about $9.2bn for a 57% stake in AmBev and will form a new company called InterbrewAmbev.

AMBEV BRANDS Brahma Skol Antarctica

The Brazilian company, meanwhile, will gain control of Interbrew's US and Canadian brewing business Labatt, as well as 30% stake in Mexican brewer Femsa.

It also will keep its separate stock market listings in the US and Brazil.

The three main shareholders in AmBev will get 25% of InterbrewAmbev, while the founders of Interbrew will control about 50%.