The Trump administration on Wednesday set new criteria for visa applicants from six mainly Muslim nations and all refugees that require a "close" family or business tie to the United States.
The move came after the Supreme Court partially restored President Donald Trump's executive order that was widely criticized as a ban on Muslims.
Visas that have already been approved will not be revoked, but instructions issued by the State Department say that new applicants from Syria, Sudan, Somalia, Libya, Iran and Yemen must prove a relationship with a parent, spouse, child, adult son or daughter, son-in-law, daughter-in-law or sibling already in the United States to be eligible.
The same requirement, with some exceptions, holds for would-be refugees from all nations who are still awaiting approval for admission to the U.S.
Grandparents, grandchildren, aunts, uncles, nieces, nephews, cousins, brothers-in-law and sisters-in-law, fiancees or other extended family members are not considered to be close relationships, according to the guidelines that were issued in a cable sent to all U.S. embassies and consulates late on Wednesday.
The new rules take effect at 8 p.m. EDT on Thursday (0000GMT on Friday), according to the cable, which was obtained by The Associated Press.