For the last week, Astan Sacko has had one more reason to be thankful she has American citizenship — and to worry about immigrant friends and neighbors who don't.

"It's going to hurt a lot of families," said Sacko, 41, who came to the United States 20 years ago from the African nation of Mali.  "We're going to have a lot of hungry kids."

She was talking about a new Trump administration plan to make it harder for legal immigrants to come here or stay here if they have used, or might use, government benefits such as food stamps, Medicaid, and public housing.

People applying for visas to enter the country, or for green cards that permit legal permanent residency, could be denied if they are deemed likely to rely on government assistance. Accepting those kinds of benefits, now or in the past, would be a "heavily weighted negative factor" in determining whether they represent what's called a "public charge."

Immigration officials would consider factors including age, health, assets, financial status, and education.

In the office of her hair-braiding salon in West Philadelphia, Sacko wondered aloud if there's much she can do to help block the proposal, which faces a 60-day period of public comment. This would be a change in government regulations, not the law, she noted, so congressmen and senators — the people she would typically call on — are less able to intervene.

Sacko is point person on the issue for AFRICOM, the local Coalition of African Communities, which advocates for African and Caribbean immigrants and refugees. She understands what new arrivals face trying to keep their families afloat, she said. She once needed food stamps herself.

Many people she knows and works with are in the process of obtaining their green cards, and now are fearful for their futures, their families, and their lives.

For more than a century, immigrants seeking to enter or live in this country have had to prove they would not become a public charge. Now, the administration wants to dramatically expand the conditions of that test.

"Those seeking to immigrate to the United States must show they can support themselves financially," Homeland Security Secretary Kirstjen Nielsen said in a Sept. 22 statement, adding that the rule would "promote immigrant self-sufficiency" and ensure newcomers "are not likely to become burdens on American taxpayers."

The Trump administration says the move will save taxpayers more than a billion dollars.

Critics say that discounts the significant financial contributions made by immigrants, including paying taxes and creating businesses and jobs.

In 2014, immigrants contributed $105 billion in state and local taxes, and nearly $224 billion in federal taxes, according to a study by New American Economy, a coalition of Republican, Democratic and independent mayors and business leaders who support immigration reform.

Deep within the 447 pages of the proposed regulation, the government acknowledges that the change could harm people, creating "worse health outcomes, including increased prevalence of obesity and malnutrition" for infants, children or pregnant women. The rule could increase rates of poverty and housing instability, and promote the use of expensive hospital emergency rooms for primary care, due to people delaying treatment.

"This is going directly at legal immigrants," said Brennan Gian-Grasso, chairman of the Philadelphia chapter of the American Immigration Lawyers Association. "You're penalizing someone for accepting benefits to which they're legally entitled."

For instance, he said, some immigrants may be working two low-wage jobs, paying taxes and contributing to the economy — but still need help from the Supplemental Nutrition Assistance Program, or SNAP, previously known as food stamps.

"What the government is essentially saying is, 'We're going to look at what you take, not what you provide,'" Gian-Grasso said.

Reaction already has been strong from pro-immigrant and family groups around the country.

"Mean. Shortsighted. Deceptive. Harmful," said Kristin Rowe-Finkbeiner, head of MomsRising, an online organization that tackles issues facing women and families.

"Yet another attack on immigrant families," said Opal Tometi, executive director of the Black Alliance for Just Immigration, which operates five offices from New York to California, and a cofounder of the Black Lives Matter Global Network.

"The Trump administration will stop at nothing to target immigrant communities," said Melissa Boteach, a senior vice president at the Center for American Progress in Washington.

Immigration advocates say the rule could contribute to the separation of immigrant families, as parents could be barred from staying in the country, while their American-born, citizen children end up in foster care.

Refugees and asylees, who entered the country on humanitarian grounds, would not be subject to the new rule.

Sacko came to the U.S. from a landlocked West African nation roughly twice the size of Texas. Half of the country's 18 million people live in poverty, and life expectancy is 60 years.

In 1999, Sacko graduated from a Mali college with a degree in legal studies, but six months later had a chance to come to America. She entered on a B-1 visa, granted to those involved in business activities, then received an F-1 student visa, she said.

She married her husband, an immigrant-turned-citizen, and together they have four American sons, ages 3 to 10. A fifth child is on the way.

Sacko bought her hair-braiding business 11 years ago, moving it a couple blocks west to 54th and Market Streets, figuring that owning a salon would help her, the people she hired, and the community.

Today, she commutes from Delaware County, home to a large African-immigrant population.

"It's really tough on us if that public charge becomes reality," Sacko said. "You'll see us in the emergency room, hungry and sick."