SAN FRANCISCO (ABC7 Los Angeles) -- California Assemblyman Phil Ting says the state "should build bridges, not walls."

The San Francisco Democrat has proposed legislation that would deny state tax breaks to any California company that opts to contract or subcontract President Donald Trump's proposed wall along the U.S.-Mexico border.

"If you want to be part of the building of that wall you can't access any of our tax breaks or incentives."

Ting says more than 375 firms nationwide have expressed interest in working on the wall.

Tax breaks California companies would forfeit under his legislation include a break for hiring new employees and a credit for buying manufacturing and research equipment.

It's the latest effort by opponents to halt what the president describes as his "big beautiful border wall."

Republican strategist and RNC member Harmeet Dhillon calls the bill a stunt.

"I'm sure there will be more than enough companies outside California willing to bid on and build the wall, so it's empty rhetoric and all it's doing is denying California employees and corporations the ability to earn a gainful living in a legal way."

Ting says Mexico is California's biggest trading partner to the tune of $25 billion a year. He says the border wall could "spur market instability" throughout California's economy. Still, he expects a challenge at the state Capitol, particularly from business groups.

He expects his bill to be heard in committee next month.