A group of truckers vowed to continue their blockade of freight shipments at the Port of Oakland through Thursday amid deepening concerns over major supply chain disruptions at one of the West Coast’s largest ports.

Truckers have been protesting since Monday against a Calfiornia labor law called AB5 which will make it harder  for independent truckers to operate.

The Port of Oakland says that operations at its shipping terminals have been "effectively shut down" since Wednesday.

A growing chorus of protesters said they planned to continue halting cargo movement until Gov. Gavin Newsom signals that he is listening to their demand to exempt truck drivers from AB 5, a state law that will require thousands of independent truck drivers to register as employees, Los Angeles Daily News reports.

The protestors are also reportedly stopping dockworkers from reaching their posts for loading and unloading ships.

The governor’s office “came back with nothing,” Navdeep Gill, the owner of a small freight company, who has been negotiating with port officials, was quoted as saying by the website.

“Give us something in writing on what the governor’s office is working on,” Gill said in an interview. “Are they buying time? Or giving us an exemption? Or what?”

Meanwhile, the Wall Street Journal quoted a spokesperon for Gov. Newsom as saying on Thursday: “Although it has been the subject of litigation, AB 5 was enacted in 2019, so no one should be caught by surprise by the law’s requirements at this time."

The stoppages are particularly hurting the region’s agricultural exporters who use Oakland as a hub, according to the WSJ.

Nina Solari, vice president of food safety and quality control at Avanti Nut Co., a family-owned walnut processor in Stockton, said two shipments scheduled to go out this week are delayed and customers are canceling orders.

“If this carries on, I don’t know what we are going to do,” Solari was quoted as saing. “We will literally be sitting on the last of our 2021 crop and not being able to ship it.”

AB5 is state law adopted in 2018 that the courts have affirmed when the United States Supreme Court denied review of the law.

The law requires companies that hire independent contractors to reclassify them as employees, but there are some exceptions in the law across industries.

The majority of truck drivers in California are owner-operator and many in this job category are concerned about their future. An estimated 70,000 truckers who own and drive their own trucks would fall under this law and they do not want to become an employee or part of a union in order to work.

Dan Schnur, a California political strategist, was quoted by Mercury News as saying: “When Newsom first signed this bill, no one really thought much about supply-chain demand."

"But that was before COVID. And before the war in Ukraine. Now it’s gotten a lot more complicated for him.”