FIRST ON FOX: Top congressional Republicans are requesting answers after the White House released a fentanyl proposal they worried would hinder critical drug enforcement during the opioid epidemic.

In a letter Thursday, the ranking members of the House and Senate Judiciary Committees outlined several criticisms of the administration's interest in ending certain quantity-based mandatory minimums.  

"While we support permanent scheduling of fentanyl-related substances, other aspects of the administration’s proposal would shield drug traffickers from pushing poisonous drugs into our communities rather than hold them accountable by imposing existing penalties," said Rep. Jim Jordan, R-Ohio, and Sen. Chuck Grassley, R-Iowa.

"We are particularly concerned that the provisions removing mandatory minimum penalties for fentanyl-related substance offenses would hinder prosecutorial efforts against serious drug traffickers, and could even incentivize sophisticated criminal organizations to import and traffic fentanyl-related substances."

WHITE HOUSE PROPOSES REMOVING PENALTIES FOR FENTANYL TRAFFICKING-RELATED OFFENSES 

Thursday's letter was addressed to the White House's Office of National Drug Control Policy (ONDCP), which informed senators of its proposal last week. Attorney General Merrick Garland and Drug Enforcement Administration (DEA) head Anne Milgram are also listed as recipients.

As Fox News reported last week, not all mandatory minimums would be excluded under ONDCP's proposal. The office's letter notes that it wouldn't exempt "FRS offenses from existing mandatory minimums for cases where death or serious bodily injury can be directly linked to the FRS that was trafficked, as is the case for any other Schedule I or II controlled substance under 21 U.S.C. 841(b)(1)(C)."

It added that DOJ "reported only eight cases with FRS [fentanyl-related substances] charges from the time temporary class scheduling was adopted in 2018 through December 2020, of which only a handful even included charges of quantity-driven mandatory minimums." 

Grassley and Jordan's letter, in turn, questioned why the administration believed a policy change was necessary "when there have only been a few quantity-based cases."

CRUZ, ROY SLAM BIDEN ADMIN OVER ‘MAN-MADE’ BORDER CRISIS AS FENTANYL DEATHS SKYROCKET

The letters came amid a spike in fentanyl deaths, which some Republicans have blamed on the administration's border policies.

April of this year alone saw a 233% increase in fentanyl seizures at the southern border, according to data released by U.S. Customs and Border Protection (CBP). Fentanyl, a dangerous opioid, is significantly stronger than heroin and the related opioid carfentanyl is even stronger than fentanyl.

ONDCP declined to comment on Thursday and has two weeks to meet the Sept. 23 deadline requested by Jordan and Grassley.

The GOP leaders also asked for a list of stakeholders that influenced the administration's proposal as well as "a list of examples in which federal law enforcement authorities have found that mandatory minimum penalties associated with fentanyl-related substances have supported criminal investigations to pursue high-level drug traffickers."

BORDER CRISIS: 233% INCREASE IN FENTANYL SEIZURES AT SOUTHERN BORDER

As ONDCP's letter noted, members of both parties supported designating FSA's as Schedule I drugs under the Controlled Substances Act (CSA). Sen. Rob Portman, R-Ohio, who praised the White House's efforts, joined Sen. Joe Manchin, D-W.Va., by introducing legislation earlier this year.

President Biden and former President Trump temporarily placed FRS under Schedule I. ONDCP's proposal would make that change permanent. It added that Congress should approve $41 billion in spending for national drug program agencies, as well as continue working on legislation designed to counter overdoses.

Portman said: "I’m pleased that the Biden administration has put forward a proposal that is consistent with bipartisan legislation I have introduced … Not only is a permanent solution critical in our battle against addiction in this country, but it is also vital in ensuring law enforcement can continue to protect our communities by bringing criminal actions against individuals who manufacture, distribute, or handle these deadly drugs."

Thursday's letter asks whether the the administration would continue supporting the Schedule I designation if "those fentanyl-related substances are not excluded by class from certain quantity-based mandatory minimum penalties associated with drug trafficking."

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It also asked "[i]f a substance scheduled under the CSA which had mandatory minimum sentences was subsequently stripped of mandatory minimums."

DOJ and DEA, which is housed within DOJ, both declined to comment.

Fox News' Houston Keene contributed to this report.