Beer sales to retailers fell 3.6 per cent for SABMiller during its first half, and volumes were again hit by price cuts and the rising popularity of speciality and imported beers, the group said in a trading statement.
The announcement suggests 2006 is likely to be remembered as another difficult year for brewers in the US, despite slight gains recently by SAB's rivals - Heineken and Anheuser Busch.
SAB, faced with a shrinking mainstream sector, has increased efforts to tap the premium, import segment.
It said it had achieved encouraging volume growth from its Leinenkugel and newly launched Peroni Nastro Azzurro beer ranges.
It has also developed a new chocolate lager to sell in the US during the Christmas period. The beer, to be called Frederick Miller Classic Chocolate Lager, contains six different malts, including a dark chocolate one.
"Given that chocolate can have literally hundreds of flavour nuances, to develop a beer which bursts with chocolate flavour is incredibly difficult," said David Ryder, vice president of Brewing, Research and Quality Assurance for the Miller Brewing Company.
"We believe this lager has the most complex chocolate taste currently on the market."
Some analysts have told mainstream brewers in the US they need to become more inventive with flavour and 'romanticise' beer in order to re-connect with consumers.
In the mean time, SAB has continued to hold up sales by performing well in emerging markets around the world.
The group recorded lager volume growth of more than 20 per cent in Russia and its Africa and Asia divisions, as well as 11 per cent in South America, helped on by a mix of universal and local brands.
China stole the show, with volumes up more than 25 per cent on the first half of last year.
In Western Europe, also a difficult market for brewers, SAB said the football World Cup in Germany this June had assisted an eight per cent volume rise. There was praise too for the firm's new-look UK business, which pushed up Peroni Nastro Azzurro sales by more than 25 per cent during the six months.