The cables were sent after President Donald Trump signed a revised executive order restricting travel from most Muslim countries on March 6.
The State Department cables, all marked "sensitive" but not classified, direct embassies to convene security and intelligence working groups to determine "a list of criteria identifying sets of post applicant populations warranting increased scrutiny."
The first two cables were sent on March 10 and 15, before a federal judge in Hawaii ordered a temporary restraining order nationwide on the travel ban on the evening of March 15.
Additional cables were sent on March 16 and March 17, revising instructions after courts blocked the executive order. The executive order prohibits citizens from Iran, Syria, Sudan, Libya, Yemen and Somalia from getting visas for at least 90 days and bars refugees from entering the US for 120 days.
The specific language calling for closer scrutiny of certain groups was sent in two different cables, including the March 17 cable, which acknowledged that courts had blocked Trump's executive order. The news about the cables was first reported by Reuters.
A State Department official said the cables were meant to provide "operational guidance to our embassies and consulates around the world. Instructions to our embassies and consulates are internal communications, which we do not share publicly."
The official did say that "the US government's national security-focused visitor screening and vetting procedures are designed to effectively identify individuals who could pose a threat to the United States," adding that "we welcome this opportunity to review and improve our systems and procedures."
Though embassies' security and intelligence officials meet regularly to review threats, the directive to identify certain groups for heightened visa requirements is seen as a significant change, staff within embassies worldwide have told CNN.
The March 15 cable included instructions on social media screening. Consular officers were told to consider posing extra questions to applicants from the identified population groups, including asking for "all email addresses and social media handles used by the applicant in the last five years."
That specific guidance was walked back in the March 17 cable, which noted the judge's restraining order and told embassies to set aside the social media instructions until they were authorized to do so.
"Consular officers must disregard the guidance" in the March 15 directive, according to the cable, unless and until the Department has received approval. Until then, "consular officers should, as always, ask additional questions as necessary to understand the applicant's answers on application forms, should thoroughly pursue any concerns that may arise during the interview, and should provide all relevant information."
The cable specified, however, that applicants from Yemen, Iran, Sudan, Syria, Somalia and Iraq should always be asked additional questions, include information about their social media accounts.
The cable also singles out those with ties to ISIS or who have been present in ISIS territory. Those applicants are mentioned separately in a paragraph titled "Mandatory Social Media Check for Applicants Present in a territory at the time it was controlled by ISIS," and must undergo a social media review as well.