In a policy change decried by Samantha Power, former U.S. ambassador to the United Nations, as “needlessly cruel and bigoted,” the Trump administration on Monday began denying visas to unmarried same-sex partners of foreign diplomats and U.N. employees—even if their home countries criminalize same-sex marriage.

“Requiring a marriage as proof of bona fide partnership is a bad and cruel policy, one that replicates the terrible discrimination many LGBT people face in their own countries.”
—Akshaya Kumar, Human Rights Watch

According to a September memo (pdf) circulated at the U.N.’s New York City headquarters, the new rules also mean that those who already reside in the U.S. and “who wish to maintain their G-4 visa must be ready to submit proof of marriage” by Dec. 31—otherwise, “they will be expected to leave the United States within 30 days.”

The move reverses a policy implemented by former Secretary of State Hillary Clinton in 2009, years before same-sex marriage became legal across the United States.

“The U.S. Mission to the U.N. portrayed the decision—which foreign diplomats fear will increase hardships for same-sex couples in countries that don’t recognize same-sex marriage—as an effort to bring its international visa practices in line with current U.S. policy,” Foreign Policy reports. “In light of the landmark 2015 Supreme Court decision legalizing same-sex marriage, the U.S. extends diplomatic visas only to married spouses of U.S. diplomats.”

In a tweet slamming the shift, Power—who, like Clinton, served under former President Barack Obama—noted that currently, only about 12 percent of U.N. member states allow same-sex marriage.

Human Right Watch’s deputy United Nations director Akshaya Kumar further explained in a blog post on Monday that in more than 70 nations, “homosexual conduct remains illegal and in many, anyone found ‘guilty’ can be sentenced to harsh punishments including years in prison or even public caning.”