The U.S. government said on Wednesday it will begin screening the social media of immigrants and visa applicants for what it called antisemitic activity, leading to swift condemnations from rights advocates, including some Jewish ones, who raised free speech and surveillance concerns.

President Donald Trump's administration has attempted to crack down on pro-Palestinian protests over U.S. ally Israel's devastating military assault on Gaza after the Palestinian Islamist group Hamas' deadly October 2023 attack.

"Today U.S. Citizenship and Immigration Services (USCIS) will begin considering aliens' antisemitic activity on social media and the physical harassment of Jewish individuals as grounds for denying immigration benefit requests," USCIS, an agency of the Homeland Security Department, said in a statement.

The step will immediately affect those applying for lawful permanent resident status, foreign students and those affiliated with educational institutions linked to antisemitic activity, it added.

"There is no room in the United States for the rest of the world's terrorist sympathizers."

The Trump administration has often labeled pro-Palestinian voices as antisemitic and sympathetic to militant groups like Hamas, Hezbollah and the Houthi rebels, whom Washington designates as "terrorists."

The administration is attempting to deport some foreign students, has revoked multiple visas and has warned universities of federal funding cuts over pro-Palestinian protests.

Protesters, including some Jewish groups, say the Trump administration conflates their criticism of Israel's actions in Gaza and support for Palestinian rights with antisemitism and support for extremism.

Rights advocates and human rights experts have condemned the Trump administration, including Wednesday's announcement which they say threatens free speech and is akin to surveillance and singling out of immigrants.

Free speech group Foundation for Individual Rights and Expression (FIRE) said the Trump administration was "formalizing censorship practices."

"By surveilling visa and green card holders and targeting them based on nothing more than their protected expression, the administration trades America's commitment to free and open discourse for fear and silence," FIRE said.

The Nexus Project, which fights antisemitism, said the Trump administration was going after immigrants in the name of tackling antisemitism and treating antisemitism as an imported problem.

Rights advocates have also raised concerns about Islamophobia and anti-Arab bias during the Israel-Gaza war. The Trump administration has not announced steps in response.