Workers began a four-week strike at the start of this week, after the company changed working hours and some pay rates.
Around 70 of the warehouses’ 130 staff are taking part in the industrial action.
Strikers will be joined by local MPs Stephen Hepburn and Emma Lewell-Buck on a march to the Tyneside firm’s HQ tomorrow, to present a letter to Dame Margaret Barbour asking for a compromise.
“We want the company to think of its family values, and to understand there are 20 members who are unable to do the late shift pattern, because of medical, transport, caring and childcare issues,” regional Unite official Fazia Hussain-Brown told City A.M.
Unite the Union expected raw materials would not be delivered to a factory tomorrow as a result of the strike, and said retailers were already feeling the effects.
Barbour declined to comment.
At the start of the strike, managing director Steve Buck said: “In order to compete as a brand on this international scale, we need to evolve with modern day working practices.”