The Trump administration is proposing a new regulation that would make it more difficult for immigrants to get green cards if they sign up for federally funded benefits such as food stamps, Section 8 housing vouchers and Medicaid, known as Medi-Cal in California.

The rule's potential impact could be massive in California, home to more than 10 million immigrants, more than any other state.

Immigrant advocates and many health care providers vowed to fight the draft regulation, which opened for a 60-day public comment period this week.

The rule, drafted by the U.S. Department of Homeland Security, would significantly increase the number of lawfully present non-citizens that immigration officers could consider a "public charge," a designation which would weigh against their eligibility to become legal permanent residents — and eventually, U.S. citizens. Unauthorized immigrants are not eligible for most taxpayer-funded benefits.

Currently, only immigrants who depend on the government for long-term cash assistance, such as Supplemental Security Income (SSI), may be considered a public charge.

Under federal law, people seeking green cards must show they are able to support themselves financially, said Homeland Security Secretary Kirstjen Nielsen in a statement.

The expansion of the public charge test would "promote immigrant self-sufficiency and protect finite resources by ensuring that they are not likely to become burdens on American taxpayers," said Nielsen.

Public charge was the most common ground to refuse admission at U.S. ports of entry in the late 19th and 20th centuries, according to Homeland Security.

Unlike previous versions leaked to the media earlier this year, the official proposal released this week clarifies that the use of taxpayer-funded benefits by U.S.-citizen children should not hurt their immigrant parents' applications for green cards.

Still, many fearful immigrant parents are likely to drop Medi-Cal for American children as well as themselves if the rule is implemented, said Erica Murray, President and CEO of the California Association of Public Hospitals and Health Systems.

"A proposed rule like this could take us backwards in terms of what's most cost effective and compassionate," said Murray, whose organization is made up of health care institutions that care for about 3 million patients per year.

Murray believes that if immigrant families decide to forgo Medi-Cal, which provides health coverage to one in three Californians, they will stop seeking preventive and primary care such as vaccines, depression treatment and the regular checkups that prevent emergency room visits. That could lead to increased costs and public health risks for the state as a whole, she said.

"The potential ramifications for the fear and confusion created by this proposed regulation could be enormous both in terms of the Medi-Cal program itself but also the overall health of communities," she said. "It's very shortsighted."

Murray and some health providers say low-income immigrants are already dropping benefits they are entitled to because they fear it could bring immigration authorities to their door, or hurt a family member's chances of getting a green card one day.

“We are already hearing anecdotally of people declining to seek services for treatments they really need out of fear it will jeopardize their immigration status,” said Murray.

But the proposed rule would not be retroactive, said Sonya Schwartz, a senior policy attorney with the National Immigration Law Center. She urged those who use public benefits to consult a trusted immigration attorney if the regulation passes and to stay enrolled for now, as the public comment period on the potential regulation unfolds.

"We are planning to get armies of people to submit comments detailing the harm that would happen," said Schwartz, who co-chairs the Protecting Immigrant Families campaign.

"I'm working with hundreds of groups across the country to push back on this rule with everything we've got."

Some immigrants would not be affected by the “public charge” expansion, including refugees and asylees, people who hold visas for victims of crime, and immigrants serving on active duty in the military.

Among the programs targeted in the proposed regulation are:

• Medi-Cal (except for an "emergency medical condition" and certain disability services)
• Medicare Part D Low Income Subsidy (which helps seniors afford prescription drugs)
• Supplemental Nutrition Assistance Program (food stamps)
• Section 8 Housing Choice Voucher Program
• Section 8 Project-Based Rental Assistance
• Public Housing