WASHINGTON>> Senate negotiators on Friday reached a deal on a proposal to overhaul the asylum system at the U.S. border with Mexico, clearing the way for Democratic and Republican Senate leaders to begin the difficult task of convincing Congress to pass a national security package that will include tens of billions of dollars for Ukraine and immigration enforcement, as well as funding for Israel and other American allies.

Sen. Chris Murphy, the lead Democratic negotiator, posted on social media Friday that a deal had been reached and that text of the bill would be released during the weekend.

Senators are still working on finishing the rest of the package, which was initiated by a request from President Joe Biden for $110 billion for wartime aid for allies, domestic defense manufacturing, humanitarian assistance for conflicts around the world and managing the influx of migrants at the U.S.-Mexico border.

Senators are preparing for a key test vote on the package next week, but it faces a steep climb through Congress. Republicans in both chambers have balked at compromises on border security policy. Senate Republicans initially demanded the package include border policy changes, but Donald Trump, the GOP’s likely presidential nominee, has become a vocal opponent of the legislation.

“Republicans said the border is a priority and we should craft a bipartisan bill to help control the border. We did that. We have a deal,” Murphy said on X.

“It’s decision time.”

The core group of negotiators has been laboring for months to craft a package that can win support from a bipartisan coalition of moderates in Congress. As they prepared to allow the details of the bill to be scrutinized, it remained to be seen whether they could cobble together the requisite votes from both sides of the aisle.

“The criticisms are based on rumors and misconceptions,” Sen. Kyrsten Sinema, an Arizona independent who was central to crafting the bill, said Thursday.

Senate Democrats, increasingly wary of the political vulnerabilities facing Biden and their party on immigration, have become more comfortable with the contours of the package, although progressive and Latino members of the House are still expected to oppose the border policy changes in droves if it passes the Senate.

The wartime aid for Israel also could divide Democrats. Sen. Bernie Sanders, an independent of Vermont, said Friday he would push to strip funding for offensive weaponry for Israel from the package while maintaining funds for defensive systems.

On the right, many conservatives oppose continued funding for Ukraine as well as compromises on border enforcement. House Speaker Mike Johnson repeatedly has declared he won’t compromise on hardline border enforcement measures, but he has said he will not pass final judgment until he is able to read the bill.

The legislation largely focuses on a challenge that Republican and Democratic administrations have grappled with: How to tamp down the growing number of people who go to the border seeking asylum, which offers protection from persecution for race, religion, political affiliation or membership in a discriminated group.

Asylum is a key part of international law and the U.S.’ability to advance human rights, but the system has become overwhelmed in recent years, creating years-long waits for asylum cases to be heard, even though many migrants fail to prove their asylum case in the end.

The bill seeks to address that, according to Sinema, by making it tougher for people to enter the asylum system, dramatically speeding up the process and denying them the ability to apply for asylum if illegal border crossings grow to become unmanageable for authorities. Most migrants who seek asylum would receive an initial interview, known as a credible fear screening, within days of arriving at the border.

They would then either be expelled from the country or given a work permit during a months-long wait to have their case heard by an immigration judge.