WASHINGTON (Reuters) – The Trump administration said on Friday that taxpayer-funded family planning clinics which primarily serve low-income Americans will no longer be able to refer patients for abortions, a move that critics vowed to challenge in court.

The new regulation was announced by the U.S. Department of Health and Human Services as part of Title X, a government family planning program that serves about 4 million people.

The program currently subsidizes health centers such as those run by the non-profit Planned Parenthood, which provides contraception, health screenings and abortions. Planned Parenthood serves about 41 percent of Title X patients and receives up to $60 million a year in federal funds for family planning services.

To continue receiving taxpayer subsidies under the program, health clinics will have to comply with the new rule. Its key elements include “prohibiting referral for abortion as a method of family planning,” the health department said in a statement, adding that the rule “eliminates the requirement that Title X providers offer abortion counseling and referral.”

The rule would also require “clear financial and physical separation between Title X funded projects and programs or facilities where abortion is a method of family planning,” the statement said. The law already bans recipients of Title X funds from using those funds to perform abortions.

Conservative groups praised the administration’s move. “We thank President Trump for taking decisive action to disentangle taxpayers from the big abortion industry led by Planned Parenthood,” said Marjorie Dannenfelser, president of the anti-abortion group Susan B. Anthony List.

But officials from the states of New York and California immediately began talking about going to court. “We will take legal action,” New York’s Attorney General Letitia James said in a statement. “These new rules are dangerous and unnecessary, and will prevent millions of Americans from obtaining the care they need and deserve.”

Planned Parenthood’s president, Leana Wen, called the new rule “unconscionable and unethical.”

“This rule compromises the oath that I took to serve patients and help them with making the best decision for their own health,” Wen said in a statement. “Patients expect their doctors to speak honestly with them, to answer their questions, to help them in their time of need.”

(Reporting by Susan Cornwell; Aditional reporting by Julian Mincer; Editing by Tom Brown)