Hundreds of bus workers who have gone on strike have staged a demonstration outside one of their depots.
Go North East (GNE) workers began an indefinite walkout on 28 October after rejecting a 10.3% pay rise offer, arguing drivers employed by the company in the North West were paid more.
The company called the protest a "distraction from the core issue that we need to resolve".
Unite union boss Sharon Graham said the pay difference was "abhorrent".
"Why are these workers getting nearly £3 less an hour, just because they're in the North East?" she said.
"It's ridiculous that these workers are getting short changed."
Drivers in the North East were getting an average of £12.83 an hour while their counterparts working for the same company in the North West were getting £15.35, she added.
The company has insisted the offer is a "fair" deal that would make its drivers the best-paid in the region.
Fresh talks to try to end the dispute broke down without a deal earlier this week.
The walkout has brought the vast majority of the major bus operator's routes to a standstill and there have been concerns for communities left cut off, the Local Democracy Reporting Service said.
Bus driver Anne-Marie Gothriley, who has worked for the firm for 18 years, said she had some "really good passengers" who were being affected by the strike.
"I feel really bad for them," she said.
"At the end of the day we're all here to provide a service and get people around.
"For all we're standing out here on strike, and it looks like we're being greedy and all that, it's affecting us just as much as it's affecting the passengers."
The union said striking workers left picket lines in Hexham, Washington, Sunderland, Consett and Percy Main to gather at GNE's Riverside depot in Dunston.
Ms Graham, Unite's general secretary, told the large crowd of chanting workers it was time to "escalate" the conflict to put pressure on the firm.
The union is calling for a 13% increase for its 1,300-plus members, and has complained drivers at Go North West earn more than £5,000-a-year more than their North East counterparts.
GNE business director Ben Maxfield said North West drivers were paid more because they had longer driver hours and more flexible schedules.
Unite had turned down the same package, he said.