The Trump administration is threatening to withhold federal funds from Washington, California and New Mexico, over claims that the three states haven't been adequately enforcing new English language proficiency (ELP) requirements for commercial truck drivers.

Starting on June 25, the U.S. Department of Transportation directed states to take truckers off the job if they can't demonstrate sufficient English language proficiency during routine traffic stops and safety inspections. Although more than 3,000 truck drivers have been removed from service under the policy nationwide, the Associated Press reports that just one driver has been taken out of service in California, even though 34,000 inspections turned up at least one ELP violation. Only four drivers in Washington, which recorded 6,000 ELP violations, have also been pulled from the job, while New Mexico has not taken any drivers out of service.

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According to Transportation Secretary Sean Duffy, the three states have 30 days to comply with the administration's ELP requirements. If they don't, they would potentially lose money from the federal Motor Carrier Safety Assistance Program, which funds a variety of road safety initiatives across the country. Duffy said that California would be denied an estimated $33 million from the program, Washington would stand to lose $10.5 million, and New Mexico would lose $7 million.

California Governor Gavin Newsom responded to Duffy's threats in an August 26 social media post, claiming that the Trump administration is "scrambling to shift blame" for issuing a federal work permit to a foreign-born truck driver in Florida accused of killing three people in mid-August, after making an illegal U-turn and slamming into a minivan.