WASHINGTON — The U.S. State Department has signaled it may revoke or deny visas to foreign nationals who publicly celebrated or mocked the assassination of conservative activist Charlie Kirk, escalating the administration’s effort to clamp down on speech it considers a threat to national security.

Deputy Secretary of State Christopher Landau announced the directive on Thursday in a statement posted to X, writing that he had instructed U.S. consular officials worldwide to “undertake appropriate action” against visa holders or applicants found to have made light of Kirk’s killing.

“I have been disgusted to see some on social media praising, rationalizing, or making light of the event,” Landau said. “Please feel free to bring such comments by foreigners to my attention so that the @StateDept can protect the American people.”

A State Department spokesperson later confirmed to ABC News that the administration views visa eligibility as a matter of national security, stressing that individuals who glorify violence or undermine U.S. interests could be denied entry. “The United States does not believe that it should grant visas to persons whose presence in our country does not align with U.S. national security interests,” the spokesperson said.

The announcement follows a wave of polarized reactions online after Kirk, 31, was fatally shot while speaking at Utah Valley University earlier this week in what officials have described as a targeted, political assassination. While many expressed grief and outrage, others — including some foreign nationals — were seen posting celebratory or dismissive remarks.

The Trump administration has expanded its oversight of visa applicants’ online activity, requiring many to make their social media accounts publicly viewable and subject to review. Officials have used AI-powered tools to flag posts deemed antisemitic, anti-American, or supportive of terrorist organizations.

In March, Secretary of State Marco Rubio unveiled a similar policy targeting foreign students and visitors found to have expressed support for Hamas, warning that their visas could be revoked immediately.

Critics of these measures, including civil liberties groups, have argued that the policies could run afoul of First Amendment principles and due process protections. Legal challenges are already underway, but the administration has countered that visas are a privilege, not a right, and can be denied at the government’s discretion.

The latest warning underscores the political stakes surrounding Kirk’s death, which has drawn condemnation from leaders across the spectrum and intensified scrutiny of online rhetoric. It also highlights the administration’s willingness to link speech abroad to immigration consequences — a move supporters say is necessary for national security, but opponents view as a troubling expansion of government authority.