NEW YORK -- The US government has ordered US embassies and consular sections worldwide to pause scheduling new interviews for student-visa applicants as it is considering requiring all foreign students applying to study in the United States to undergo social media vetting, local media cited a cable dated Tuesday and signed by Secretary of State Marco Rubio.

"Effective immediately, in preparation for an expansion of required social media screening and vetting, consular sections should not add any additional student or exchange visitor visa appointment capacity until further guidance is issued, which we anticipate in the coming days," the cable said.

The cable did not directly specify what future social media vetting would screen for.

The US government had earlier imposed some social media screening requirements, which were largely aimed at returning students who may have participated in protests against Israel's actions in Gaza. The new move is a significant expansion of previous such efforts.

The freeze may impact thousands of international students and potentially contributes to declining international enrollment in US higher education institutions, local media reported.

The US government has used a variety of rules to target universities, especially elite and liberal ones such as Harvard University, and accuses them of allowing antisemitism to flourish on campus. At the same time, it is carrying out immigration crackdowns that have resulted in arrests of a number of students.