White House press secretary Jen Psaki has blamed Republican senators for holding up President Joe Biden’s nominee to lead the Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF).

Speaking at a press conference on Wednesday, Aug. 4, Psaki said that she is “disappointed” that the Senate Republicans are “moving in lockstep” to block the confirmation of former ATF agent David Chipman to serve as the ATF’s next director, Washington Examiner reported.

Asked what President Biden is doing to lobby support for Chipman in the Senate, Psaki declined to read out any “private conversations” Biden has with legislators but said that “we knew this wouldn’t be easy.”

“ATF hasn’t had a confirmed director in six years, and only one confirmed director since the position became Senate-confirmable, so we’ve been eyes wide open into the challenge from the beginning,” Psaki said.

She added that “We are disappointed by the fact that many Republicans are moving in lockstep to try to hold up his nomination and handcuff the chief federal law enforcement agencies tasked with fighting gun crimes.”

Psaki said Chipman has 25 years of distinguished service as an ATF agent and has the skills and experience to revitalize the bureau’s work to crack down on gun trafficking and keep guns out of the hands of criminals. She claimed that the GOP’s stalling the confirmation of Chipman “speaks volumes to their complete refusal” to tackle crime.

According to The Hill, Chipman faces resistance from Republican senators who claim his ties to the gun violence prevention group Giffords make him too extreme to run a federal agency tasked with enforcing certain gun laws.

Even a handful of Democrats have also yet to offer their support to Biden’s ATF pick. Sens. Jon Tester (D-Mont.), Angus King (I-Maine), and Joe Manchin (D-W.Va.) are among those who have not publicly said how they would vote for Chipman.

In April, Biden picked Chipman as the nominee when he hailed Chipman as “the right person, at this moment, for this important agency” as his administration is seeking to combat gun violence in the wake of mass shootings in Atlanta and Boulder, Colorado.

But Chipman’s rocky road to a confirmation vote is expected to complicate Biden’s plans to address rising crime and gun violence.

According to The Hill, the six-year drought in confirming an ATF director reflects the sharp divisions between Republicans and Democrats over gun laws.