Negotiations between the Biden administration and Senate negotiators have stalled over the use of humanitarian parole authority, a tool that allows the administration to grant temporary admission to certain migrants into the United States.

The administration has relied on parole extensively in recent years, particularly to admit Afghans and Ukrainians fleeing conflict. However, Republicans argue that the administration is overusing parole and seeking to restrict its use.

“The administration is using parole as a mass tool to permit people into this country,” said Sen. Thom Tillis (R-NC), a key negotiator in the talks. “We simply don’t trust them to use it responsibly.”

Democrats, on the other hand, argue that parole is a vital tool for addressing humanitarian crises and managing the border. They are pushing to retain the administration’s current authority to use parole.

“The president needs the authority to come to the aid of people who are dying,” said Senate Majority Whip Dick Durbin (D-IL). “To eliminate parole would be to tie his hands.”

The impasse over parole has threatened to derail broader negotiations on a border security bill. The bill would also include funding for Ukraine and Israel, as well as provisions to reform the asylum system.

“A lot is riding on a border security agreement,” Durbin said. “I just hope they resolve it soon because what is at stake is assistance for Ukraine to stop Putin and assistance to Israel to try to bring an end to the violence that is going on there.”

Negotiators have made progress on other aspects of the bill, such as raising the credible fear standard for migrants seeking asylum. However, the deadlock over parole could jeopardize the entire package.