The Port of Oakland Truckers Association announced on Monday that drivers will walk off the job as early as next week if they don’t get financial help meeting new clean-air standards.

The association wants the port to pay an emissions fee of $50 per load to help offset the cost of upgrading, plus a $50 per hour fee after the first two hours a trucker has to wait in line picking up a load.

Oakland Mayor Jean Quan has said she would look for extra city money to help, but truckers are threatening to walk out next week in what would be the third work stoppage in since August.

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