Workers who deliver beer, lager and soft drinks to pubs, clubs - and Downing Street - will stage a 24-hour strike tomorrow in a row over jobs.
Unite said the walkout by its members at Kuehne + Nagel Drinks Logistics (KNDL) from 10am would cause "significant disruption" to thousands of sites.
Pubs, clubs, airports, theatres, mainline railway stations, football grounds and Parliament will all be hit, said Unite.
KNDL said it had contingency plans and would seek to minimise disruption to deliveries.
The firm added it had been consulting employees for a number of years over the need to adapt its business model.
Picket lines will be mounted at depots across the country.