US President Donald Trump’s administration has unveiled a new rule that could prohibit hundreds of thousands of people from permanently residing in the US because they are too poor, Reuters reported.

The long-awaited rule put forward by Trump’s leading immigration aide, Stephen Miller, enters into force in mid-October and will reject applicants for temporary or permanent visas for failing to meet income standards or to receive government assistance such as social security, food stamps, public housing or Medicaid health insurance.

Ken Cuccinelli, the acting director of U.S. Citizenship and Immigration Services (USCIS) said at a White House media briefing announcing the rule that “the law has required foreign nationals to rely on their own capabilities and the resources of their families, sponsors and private organizations in their communities to succeed”

Experts believe that this may be the most radical of all the anti-immigration measures of the Trump administration. Immigrant advocates criticized the plan as an attempt to cut back on legal immigration, without Congressional approval, to change US law.

Under the new rules, over half of all applicants for family green cards will be denied. In 2016, approximately 800,000 green cards were issued.

Most non-resident immigrants are not eligible to participate in basic assistance programs until they receive a green card, but a new rule published by the Ministry of Homeland Security broadens the definition of public prosecution, which could disqualify more people.

Applicants will need now to show a higher income level to obtain a visa, and this rule significantly expands the list of state benefits that deprive them of the right to obtain a residence permit in the US.