California Governor Gavin Newsom announced on Wednesday evening his intention to take legal action against the Trump administration for deploying immigration officers to San Francisco.

“If you deploy troops to San Francisco, we will take you to court, @realDonaldTrump,” Newsom declared in a post on X, accompanied by a video from a press briefing.

Newsom emphasized, “Our response will be both determined and strategic.” Holding up a stack of documents, he added, “This lawsuit is ready to be filed instantly should there be any attempt to station military forces in one of the nation’s iconic cities, San Francisco.”

The governor applauded the city for its reduced homicide rates and economic achievements, noting that “only Donald Trump can jeopardize that progress.”

“We will stand firm and articulate in our opposition,” he stated confidently. “We have a history of prevailing in court, and we intend to continue that success.”

The administration dispatched 100 agents with U.S. Customs and Border Protection and from Coast Guard Base Alameda, the San Francisco Chronicle reported. They are expected to arrive on Thursday.

Trump announced over the weekend that he would send federal officials to San Francisco “and we’ll make it great,” he told Fox News.

“We’re going to go to San Francisco,” Trump added. “The difference is they want us in San Francisco.”

Newsom and San Francisco Mayor Daniel Lurie (D) spoke out against any deployment of federal agents in the city.

“California has seen enough. President Trump and Stephen Miller’s authoritarian playbook is coming for another of our cities, and violence and vandalism are exactly what they’re looking for to invoke chaos,” Newsom posted on X.

Lurie told The Associated Press last week that the city is safe.

“We got this in San Francisco,” he added.

But on Monday, Lurie said San Francisco will welcome more federal help to arrest drug dealers and disrupt drug markets. Other than that, sending in the National Guard was out of the question.

“The National Guard does not have the authority to arrest drug dealers — and sending them to San Francisco will do nothing to get fentanyl off the streets or make our city safer,” Lurie told the AP in a statement.

In June, Trump sent the National Guard to Los Angeles after Immigration and Customs Enforcement raids south of the city led to local protests.

The president has since deployed soldiers to Illinois, Portland, Ore., Memphis, Tenn., and Washington, D.C. within the first nine months of his second term.