BERKELEY (CBS13) – U.S. Senator Kamala Harris was supposed to deliver the keynote speech at Saturday’s spring commencement ceremony at UC Berkeley, but now she will not attend due to an ongoing labor dispute.

The school made the cancellation announcement Monday, saying: “We regretfully share the news that, after much consideration, U.S. Senator Kamala Harris has decided not to speak at Saturday’s commencement ceremony at UC Berkeley due to a UC-wide speaker boycott called by AFSCME Local 3299.” Chancellor Carol Christ will now deliver the keynote address.

Senator Kamala Harris’s office issued the following statement: “Due to the ongoing labor dispute, Sen. Harris regretfully cannot attend and speak at this year’s commencement ceremony at UC Berkeley. She wishes the graduates and their families a joyous commencement weekend and success for the future. They are bright young leaders, and our country is counting on them.”

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AFSCME Local 3299 called for the boycott in mid-April due to “contract negotiations and post-impasse mediation procedures being exhausted.” Union members voted with 97% approval to authorize a strike. They also asked all speakers invited to participate in UC graduation events to boycott until the labor dispute is resolved.

AFSCME is the University of California’s largest employee union, representing more than 24,000 employees.