Supplies of two of the most popular beers in Belgium could be affected by an industrial dispute.
A week-long blockade at the headquarters of Anheuser-Busch InBev in Leuven is threatening supplies of Stella Artois and Leffe.
Anheuser-Busch InBev is the world's biggest brewing company.
Belgian supermarkets and bars say stocks are running low.
The BBC reports the unions are against plans by the company to cut more than 250 of 2700 jobs in Belgium.
Anheuser-Busch InBev announced this week a plan to cut 800 jobs across western Europe, 10% of its 8000-strong workforce in the region.
The company said the move was a response to falling beer sales, with the layoffs spread across Belgium, Germany, Britain, the Netherlands and Luxembourg.
Anheuser-Busch InBev was formed in 2008 when Belgium-based InBev bought Anheuser-Busch, the owner of Budweiser, and the largest brewer in the US.
InBev was formed in 2004 when Belgian Interbrew merged with Brazil's AmBev.