Another strike by workers at food giant Heinz is "inevitable" after talks aimed at resolving a row over pay broke down, union leaders have said.
Members of Unite at the firm's site in Wigan will walk out for 24 hours from the evening of December 29, with further industrial action expected in the new year.
Heinz said it revised its pay offer during a meeting with the union held at the conciliation service Acas, maintaining the deal was worth 4% this year and 3% next year.
Unite said the offer was worth 3.3% and 3%, adding it was effectively a wage cut because the suggested deal was below the rate of inflation.
A Heinz spokesman said: "We are extremely disappointed with this outcome. What we are proposing addresses a number of key points we received in extensive feedback from our employees.
"We have worked hard to improve what we already believed was a very fair offer in an attempt to try and bring an end to the dispute. Our offer is well above our competitors and UK average weekly earnings, which are increasing by 1.7%. Heinz remains a top-tier employer and payer.
"We will seek to arrange further meetings with the union to resolve the dispute but the ongoing industrial action will leave many totally perplexed.
"Supplies of Heinz beans and soups continue to be available, and we are working as hard as we can to keep up with the huge demand as a result of the exceptional cold weather."
Jennie Formby, Unite's national officer for the food sector, said: "Heinz must start listening to their workers if they want to avoid an escalation to this dispute. Our members won't be palmed off with a second-rate deal that in real terms represents a cut in their standard of living when Heinz is making such excellent profits and continuing to reward senior executives and shareholders so generously.
"Unite is still willing to sit down with the company to negotiate a settlement, as we have been from the beginning of this dispute, but management has to recognise that simply rehashing the existing deal won't be acceptable to our members."