The US State Department told embassies and consulates they must vet student visa applicants for "hostile attitudes towards our citizens, culture, government, institutions, or founding principles" but said they should resume appointments that were paused in late May.

The new guidance was sent to US diplomatic posts worldwide in a cable seen by CNN Wednesday.

It says the vetting will look at student and exchange visa applicants' "entire online presence." Applicants will be asked to set their social media profiles to public as part of the new vetting, and the cable notes that "limited access to, or visibility of, online presence could be construed as an effort to evade or hide certain activity." It comes as the Trump administration has taken significant actions that are likely to deter international students from coming to the US.

It has aggressively revoked student visas and specifically targeted Harvard University.