Tesco could be rocked by Christmas disruption as trade unions announced that industrial action would go ahead at 14 depots.
Usdaw revealed that members had rejected a four per cent pay rise, and will join Unite workers striking later this month.
Tesco, which accounts for 27.7 per cent of the grocer market, has insisted the wage increase was “fair and competitive”.
However, at two per cent below the retail price inflation rate, Unite claimed it was a “real terms pay cut”.
READ MORE: Tesco sees highest jump in market share since 2007
Usdaw members voted to take action at warehouses in Daventry, Goole, Hinckley, Lichfield, Livingston, Peterborough, Southampton, plus two sites in Magor.
National officer Joanne McGuinness said members had “sent a clear message”.
“We hope that the company is listening and that they will return to the negotiating table with a better deal,” she continued.
“Industrial action and possible stock shortages in stores in the week before Christmas can be avoided.
“It needs the company to engage positively in talks with Usdaw and we stand ready to reopen negotiations.”
Unite workers will begin their strike in Antrim, Belfast, Didcot and Doncaster on December 16.
Those in the Doncaster and Didcot depots will return to work for two days on December 18, giving Tesco the chance to strike an eleventh-hour deal.
Unite general secretary Sharon Graham said: “Our members have gone above and beyond the call of duty to keep Tesco’s shelves filled throughout the pandemic.
“At the very least the UK’s largest and wealthiest retailer should be making our members a decent pay offer.”
The union is also balloting members at Tesco’s distribution hub in Livingston.
However, the supermarket is said to have threatened to cut bonuses and sack staff who walk out.
A Tesco spokeswoman told the BBC that it would be able to keep shelves stocked over the festive season.
“Our distribution colleagues have worked tirelessly through the pandemic in order to keep products moving for customers,” she said.
“The pay offer we have made is a fair recognition of this.”
The spokeswoman added that the wage boost was one of the highest awards made in Tesco’s distribution business in the last 25 years.
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