Bus strikes are set to go ahead after workers rejected their latest pay offer.
Go North East workers will be going on indefinite strike from Saturday 28 October.
Unite the union said workers were escalating the industrial action after rejecting the "insulting" pay offer of 10.3%.
Workers have already staged two week-long strikes this month, causing disruption for passengers.
Go North East had agreed a deal with Unite which was put to members this week. However, the offer was rejected by 81% on a turnout of 93%.
The bus company had said the deal would see drivers paid £14.15 an hour, alongside a guaranteed above-inflation pay increase next year.
The union said members were paid up to 20% less than those working for Go North West in Manchester, where drivers are paid up to £15.53.
Unite regional officer Mark Sanderson added: “We have repeatedly asked Go North East for a fair pay increase and again and again dragged their feet and refused to make a decent pay offer. We have drivers pushed to the brink of tiredness, working all hours God sends and skipping meals to make ends meet – yet their employer shows nothing but callous disregard for their wellbeing.
"Go North East have massively misread the strength of feeling from their workers on this issue and Unite will be backing them the whole way.”
Ben Maxfield, Go North East business director said, “We are baffled. Drivers wanted an above inflation deal, no changes to conditions and top-of-the market rates. We responded to each and every one of those demands, which makes it hard to understand why the union would press ahead with 12-weeks of industrial action”.
“This has become a strike entirely of the union’s own making”.
He added: “Immediately after learning of the ballot outcome, we appealed to the union to reconsider and suspend the strike. Unfortunately, this was met with a flat refusal."
The strike means there will be no Go North East buses running for the next 12 weeks, except for contracted school services.
The union has said 60% of almost 1,000 members who responded to its survey said they had cut back on essentials like food and energy while nearly a fifth reported skipping meals or not being able to pay rent or mortgage.
Three quarters reported working "excessively long hours", according to the union.
Unite general secretary Sharon Graham said: “Go North East are betraying their workers and are now responsible for the disruption caused to people living in the North East."
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