Planned Parenthood announced on Monday that it was withdrawing from Title X, the federal family planning program that provides affordable birth control, over a new Trump administration rule that bars clinics in the program from giving abortion provider referrals.

Calling the provision an "unethical gag rule," the reproductive health care network said it was dropping out of the program rather than complying with it.

The Title X program serves about 4 million women nationwide through grants to healthcare providers that fund family planning services, including birth control, pregnancy tests and STD screening. Grant recipients were given a deadline of Monday to explain how they would comply with the new rule.

Planned Parenthood's decision to leave Title X could affect more than 1.5 million low-income women who use the provider. The organization is Title X's largest grant recipient, serving 40 percent of all Title X patients.

Planned Parenthood's move is the latest in a years-long fight with the White House over the changes to Title X. Last week, Planned Parenthood asked the 9th U.S. Circuit Court of Appeals for an injunction to block the policy, warning in a letter that it would have "no option but to withdraw" if no emergency action was taken by the court.

On Monday, Planned Parenthood in a statement urged Congress to pass a spending bill that would "reverse the harmful rule and restore access to birth control, STD testing, and other critical services to people with low-incomes."

“I want our patients to know: while the Trump administration may have given up on you, Planned Parenthood never will. Our doors are open today, and our doors will be open tomorrow," said Alexis McGill Johnson, acting President and CEO of Planned Parenthood Federation of America.

“We believe that the Trump administration is doing this as an attack on reproductive health care and to keep providers like Planned Parenthood from serving our patients. Healthcare shouldn’t come down to how much you earn, where you live, or who you are," she added.

White House deputy press secretary Judd Deere said in a statement that that organization had "decided that aborting innocent unborn lives is more important than receiving Federal funding. This President will continue to protect life, women’s health, and fight for our most vulnerable.”

In a May 2018 speech, President Donald Trump touted the new rule as a "historic announcement" that fulfilled a campaign "promise."

"For decades, American taxpayers have been wrongfully forced to subsidize the abortion industry through Title X federal funding," Trump said, according to a transcript of the remarks.

The Title X program was created nearly 50 years ago to fill in gaps in health care access and affordability, particularly for those in rural or otherwise underserved areas. Most of its patients are people of color, Hispanic or Latino, according to Planned Parenthood.

The Trump administration's rule prohibiting what health care providers can say about abortion has also been opposed by the American College of Obstetricians and Gynecologists, among other public health associations.