A host of 2020 Democratic presidential candidates vehemently criticized the Hyde Amendment -- a federal law blocking taxpayer funding for abortion -- on Wednesday in an apparent rebuke of former Vice President Joe Biden's reported support for the measure.

While many in the Democratic field did not tweet about Biden by name, New York City Mayor Bill de Blasio flat-out said Biden shouldn't be the Democratic presidential nominee.

"If you don’t support repeal, you shouldn’t be the Democratic nominee," he said while retweeting NARAL's condemnation of Biden's apparent stance on the issue. At the beginning of 2019, De Blasio's city lit up the One World Trade Center, at the direction of the governor, in celebration of a bill that would allow abortions up to the point of birth.

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Others were more subtle in opposing the former vice president's reported stance, tweeting general support for a repeal amid a Wednesday report that Biden still supported the amendment.

"Reproductive rights are human rights, period. They should be non-negotiable for all Democrats," Sen. Kirsten Gillibrand, D-N.Y., said. Sens. Gillibrand and Kamala Harris, D-Calif., were just two of many Democrats to call for the Hyde Amendment's repeal as state and federal policies posed a growing threat to abortion access.

"The Hyde Amendment is a threat to reproductive rights that punishes women and families who already struggle with access to adequate health care services," Sen. Cory Booker, D-N.J., added.

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Controversy over the issue seemed to represent the first major divide among the declared 2020 candidates. Biden has received criticism from Rep. Alexandria Ocasio-Cortez, D-N.Y., for not going far enough on climate change but has generally been able to avoid attacks related to the perception that he's a moderate.

Biden, the American Civil Liberties Union reported in May, told a woman that he wanted to repeal the Hyde Amendment but something apparently changed as his campaign told NBC News the 2020 frontrunner still supported the policy.

Federal abortion funding will likely become an even greater issue as the Democratic convention approaches. Many of the 2020 candidates have proposed "Medicare for All," which would vastly expand the government's role in health care and likely mandate government-provided abortions.

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In an op-ed for Fox News, Reps. Steve Scalise, R-La., and Greg Walden, R-Ore., blasted the provision as flying in the face of decades of consensus surrounding the abortion issue.

"Democrats are actively trying to reverse a 40-year, bipartisan protection against federal taxpayer-funded abortions. They’d also force doctors and nurses to terminate a baby’s life," they said.

According to polling from January, the majority of Americans opposed taxpayer funding of abortions (54 percent opposed or strongly opposed, 39 percent support or strongly support).

Although Hyde blocks the majority of abortion funds, it allows funding for cases of rape, incest and threat to the life of the mother. Pro-life advocates have also taken issue with state Medicaid reimbursements as effectively funding abortion with taxpayer money. They've also argued that taxpayers effectively fund abortions through the federal government's decision to fund Planned Parenthood.

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Sen. Bernie Sanders, I-Vt., who polls second to Biden for the 2020 nomination, specifically pledged to repeal Hyde as part of his Medicare for All plan.

"There is no #MiddleGround on women's rights. Abortion is a constitutional right. Under my Medicare for All plan, we will repeal the Hyde Amendment," he said.

Those comments came amid broader tension within the Democratic Party, which faced dissenting members on abortion and renewed scrutiny over its inclusion of pro-life voices after its 2016 electoral loss.

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While Democratic congressional leaders have accepted the existence of pro-life members, the party as a whole has adamantly pushed a pro-choice position. The issue came to a head when Louisiana's Democratic governor signed one of the many restrictive "heartbeat' bills that would ban abortion in states after a doctor can detect a heartbeat.

Progressive Caucus co-chair Pramila Jayapal, D-Wash., indicated that pro-life Democrats should face "strong primary challenges" and not receive funds from the Democratic Party's main congressional campaign committee.

The issue seemed to divide Republicans, although not as noticeably, with the president and others expressing hesitation towards bans, like Alabama's, that excluded exceptions for rape or incest.

Jeanne Mancini -- who leads March for Life, the nation's largest pro-life demonstration -- welcomed Biden's reported position and defended Hyde as the "single most impactful pro-life public policy."

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“The Hyde Amendment is the single most impactful pro-life public policy, saving well over 2 million lives since being enacted. It is very popular with mainstream America and up until recently was a bipartisan policy," she said in a statement provided to Fox News.

"We welcome former VP Biden’s endorsement of the Hyde Amendment, and we would welcome the opportunity to discuss with him other policies related to the protection of innocent, unborn life - policies he supported when he was first in Congress. Abortion is a human rights issue, and ought to be a bipartisan issue as well.”

Fox News' Paul Steinhauser contributed to this report.