A move to transfer 500 Sainsbury’s HGV drivers over to Wincanton has erupted in a row with a threat from a trade union that any strike action will cause “severe disruption”.

The affected lorry drivers, based in Essex and Birmingham and responsible for deliveries from distribution centres in Coleshill and Waltham Abbey to the supermarket’s stores, will be balloted for strike action over plans to outsource their jobs.

The drivers are currently directly employed by Sainsbury’s, but the Unite union said there was a plan in place to move them all over to Wincanton by the end of April in an effort to outsource staff “on the cheap”.

The union also claimed that the transfer would result in the workers no longer being eligible for benefits they receive as Sainsbury’s employees, including a discount card worth up to £1,600 a year in savings, as well as share save and incentive schemes.

Unite national officer Matt Draper said: “There is still time to resolve this dispute before it escalates. But for that to happen, Sainsbury must get back around the negotiating table and put forward a deal our members can accept.”

A Sainsbury’s spokeswoman said: “We are committed to further talks.

“In the meantime we can reassure our customers we have contingency plans in place to minimise any disruption, should the action go ahead.”

The ballot for strike action opens on Monday (26 February) and closes on 11 March.

Wincanton was approached for comment.