Former vice president Joe Biden holds a campaign event at the IBEW Local 490 on Tuesday in Concord, N.H. (Scott Eisen/Getty Images)

Two of the most influential abortion rights groups in national politics are criticizing former vice president Joe Biden over his support for the Hyde Amendment, which prohibits federal funds from being used on abortion in most circumstances.

The backlash came in response to an NBC News report that Biden continues to support the rule, which allows for exceptions only in the case of rape, incest or to save the life of the mother.

Biden, who is currently leading in early polls for the 2020 Democratic presidential nomination, would back repealing the amendment “if abortion avenues currently protected under Roe were threatened,” his campaign told NBC News.

In a statement Wednesday, Ilyse Hogue, president of the abortion rights group NARAL, said there is “no political or ideological excuse” for Biden’s support for the amendment, which she said “translates into discrimination against poor women and women of color plain and simple.”

“His position further endangers women and families already facing enormous hurdles and creates two classes of rights for people in this country, which is inherently undemocratic,” Hogue said.

Stephanie Schriock, the president of Emily’s List, a political action committee that works to elect Democratic women who support abortion rights, also issued a statement calling it “unacceptable” for a major Democratic White House contender to support the Hyde Amendment.

“We hope that Vice President Biden will reconsider this position and what it means to millions of women,” Schriock said, noting that the amendment “effectively bans abortion for women on Medicaid.”

A Biden campaign spokesman did not immediately respond to a request for comment.

The flurry of criticism over Biden's position on abortion rights was only the latest conflict between the former vice president and liberal elements of his party, who in recent days have sought to recapture the upper hand in the presidential contest. Fellow candidates Sens. Elizabeth Warren (D-Mass.) and Bernie Sanders (I-Vt.) defended their more liberal stances and criticized Biden for his centrist positions over the weekend during a California state party convention; the most substantial criticism to date.

Biden's stance on the issue puts him at odds with most of the 2020 Democratic presidential field as well as with the Democratic Party’s platform. In 2016, the party amended its platform to include a plank calling for the repeal of the Hyde Amendment, describing it as among the “federal and state laws and policies that impede a woman’s access to abortion.”

“The Democratic Party platform is crystal clear in supporting the right to safe, legal abortion and repealing the Hyde Amendment, a position held by the majority of voters,” Kelley Robinson, executive director of the Planned Parenthood Action Fund, said in a statement Wednesday afternoon taking aim at Biden’s position. “Supporting Hyde isn’t good policy or politics.”

A 2016 Harvard Public Health/Politico poll showed that 58 percent of Americans opposed changing the current policy in order to allow Medicaid funds to be used to pay for abortions. Among Democratic likely voters in the 2016 election, 55 percent favored changing the law while 37 percent opposed it.

The report on Biden’s support for the Hyde Amendment prompted several other 2020 Democratic presidential candidates to quickly weigh in.

“There is #NoMiddleGround on women’s rights,” Sanders said in a tweet. “Abortion is a constitutional right. Under my Medicare-for-all plan, we will repeal the Hyde Amendment.”

Former congressman Beto O’Rourke (Tex.) shared a video of himself calling for the amendment’s repeal. “No matter your income or where you live, every woman should have access to health care, including abortion,” he said.

Julián Castro, the former mayor of San Antonio and housing secretary in the Obama administration, also tweeted his opposition to the amendment on Wednesday, as did Sen. Kamala D. Harris (Calif.), Sen. Kirsten Gillibrand (N.Y.), Washington Gov. Jay Inslee, Rep. Tim Ryan (Ohio) and New York Mayor Bill de Blasio.

In her statement, Hogue noted that Biden's stance contrasted with that of the other White House contenders.

“At a time where the fundamental freedoms enshrined in Roe are under attack, the 2020 Democratic field has coalesced around the Party’s core values — support for abortion rights, and the basic truth that reproductive freedom is fundamental to the pursuit of equality and economic security in this country,” she said. “Differentiating himself from the field this way will not earn Joe Biden any political points and will bring harm to women who are already most vulnerable.”

Last month, the American Civil Liberties Union tweeted a video of one of its volunteers questioning Biden on whether he supported the Hyde Amendment. Biden appeared to advocate for doing away with it.

“Right now, it has to be — it can’t stay,” Biden told the volunteer. Biden’s campaign later told The Hill newspaper that the former vice president misheard and thought the volunteer was asking him about the Mexico City policy, which bars U.S. aid to any overseas organization that performs abortions or proactively mentions the procedure.

Scott Clement contributed to this report.