California Gov. Gavin Newsom said Wednesday he was prepared to sue the Trump administration in a “nanosecond” if the White House moved forward with the deployment of the National Guard to San Francisco.

“Send troops to San Francisco and we will sue you,@realDonaldTrump,” Newsom wrote plainly in a post on X.

“Quite literally, this is the lawsuit that I will file within a nanosecond of any efforts to send the military to one of America’s great cities,” he added during a press briefing, while holding up a copy of the legal documents.

Newsom’s statement comes as the Trump administration is preparing to dispatch more than 100 federal agents to the San Francisco Bay Area this week as it ratchets up immigration enforcement in the region, according to The San Francisco Chronicle.

These agents will include personnel from U.S. Customs and Border Protection and are expected to begin arriving as of Thursday.