President Donald Trump's administration began denying visas to the unmarried, same-sex partners of foreign diplomats and officials and employees of the United Nations this week — making marriage a requirement to be eligible for a visa.

The policy was made effective Monday.

It comes despite the fact that the majority of countries do not recognize same-sex marriage and many same-sex couples face prosecution in their own countries.

The shift was detailed in a memo circulated at the United Nations' headquarters in New York last month but unveiled in July, according to the State Department.

The policy shift gives the same-sex partners of foreign diplomats and U.N. workers until the end of the year to get married or leave the country.

The State Department said in a briefing Tuesday that the policy will affect about 105 families in the USA, 55 of which have links to various international organizations. It was not clear how many foreign diplomats and U.N. employees with pending U.S. posts will be affected by the policy change.

Twelve percent of the 193 U.N. member states represented in New York allow same-sex marriage, according to Samantha Power, a former U.S. ambassador to the United Nations who served under President Barack Obama.

The Trump administration said the new policy is more consistent with the Supreme Court ruling in 2015 that legalized same-sex marriage. The heterosexual partners of foreign diplomats and U.N. employees are also not eligible for U.S. visas.

Critics of the move argued the policy would create hardship for gay couples from countries that ban same-sex marriage or offer only civil unions. Those who marry in the USA to secure their visa status could face criminal proceedings once they return to their home nations.

"Those not yet in the country will need to show they’re married to secure a visa, potentially forcing those living in countries without marriage equality to choose between a posting at UN headquarters or family separation," Akshaya Kumar, deputy U.N. director at Human Rights Watch, wrote in a blog post.

UN Globe, which advocates for non-discrimination of LGBTI staff at the United Nations and in its peacekeeping operations, said it was an "unfortunate change in rules, since same-sex couples, unlike opposite-sex couples, have limited choices when it comes to marriage."

Power, the former ambassador, described the policy in a tweet as "needlessly cruel and bigoted." The State Department said the rule change would promote equal treatment. It said it recognized that not all countries permit same-sex marriage and it was prepared to work with individual cases to find a solution for those not able to marry.

But Diane Klein, a legal scholar at the University of La Verne who first wrote about the policy change in a blog post in July, said: "What remains unclear, both to employees inside affected agencies, and to legal commentators from the outside, is whether visa holders who marry their partners in the U.S., but whose marriages would not be recognized by their home countries, will enjoy continuing access to these partner visas."

On Friday, nearly 120 House Democrats signed and sent a letter to Secretary of State Mike Pompeo pressing him and the administration to reverse what they say is a discriminatory policy.

“The United States must maintain its historical moral leadership on all human rights issues, including those affecting LGBTQI people,” wrote the lawmakers. “This policy sends the wrong message that the U.S. is not welcoming of all people.”

“It also needlessly excludes UN personnel, and places an unnecessary burden on diplomats from countries that do not currently allow same-sex marriage. We urge the State Department to reconsider its decision,” the lawmakers added.

Rep. Ted Deutch, D-Fla., who was among the lawmakers to sign the letter, said it is “particularly offensive that [the administration] would dare announce this policy in the name of equality.”

“Progress has been made in this country despite, not because of, this Administration,” he said. “Secretary Pompeo should swiftly reverse this decision and lift the burden on partners of foreign diplomats coming from countries where same-sex marriage is illegal."

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