As a bipartisan deal to secure the U.S.-Mexico border and provide military aid to Ukraine and Israel appeared doomed Tuesday, President Joe Biden pleaded for Republicans in Congress to “reconsider blowing this up.”

The speech came shortly before Senate Republican Leader Mitch McConnell, R-Ky., declared the bill all but dead, saying at a GOP leadership press conference that due to House GOP opposition, "we have no real chance here to make a law."

The president accused GOP lawmakers of “caving” to former President Donald Trump, the front-runner for the Republican nomination who has urged Republicans to reject the bill.

“All indications are this bill won't even move forward to the Senate floor,” Biden said during a brief White House speech. “Why? A simple reason:  Donald Trump. Because Donald Trump thinks it’s bad for him politically. He'd rather weaponize this issue than actually solve it.

“Republicans have to decide: Who do they serve, Donald Trump or the American people?” he added.

If the bill dies, the president vowed he’d remind people “every day” until the election that “the reason the border is not secure is Donald Trump and his MAGA Republican friends.”

Biden said the deal represents “the most fair, humane reforms in our immigration system in a long time and the toughest set of reforms to secure the border ever.”

He touted provisions that would add 1,500 agents at the border, install 100 machines to detect and stop fentanyl smuggling and hire 100 new immigration judges, which Biden said would help cut the wait for asylum proceedings down from five to seven years to six months.

“The bottom line is this bipartisan bill is a win for America because it makes important fixes to our broken immigration system,” Biden said. “And it's the toughest, fairest law that’s ever been proposed relative to the border.”

Two days after it was unveiled, the bill appeared all but dead Tuesday, as House Republicans and many GOP members in the Senate have come out against it. 

At a Senate GOP leadership conference Tuesday afternoon, McConnell said that "there are other parts" of the bill that are "extremely important," urging lawmakers to pass aid to Israel, Ukraine and Taiwan and saying it's on Senate Majority Leader Chuck Schumer, D-N.Y., to "repackage" the deal to include international aid -- despite the fact that it was Republicans who initially called for Ukraine and and border security to be linked.

When asked if he misread the whims of his conference in crafting the bill, McConnell insisted that it was "our side that wanted to tackle the border issue."

"Things have changed over the last four months, and it's been made perfectly clear by the speaker that he wouldn't take it up even if we sent it to him and so I think that's probably why most of our members think we ought to have opposition" to Wednesday's procedural vote," McConnell added, before reiterating the desire to move on with the international aid.

Sen. Chris Murphy, D-Conn., one of three senators who negotiated the deal along with Biden administration officials, told reporters Tuesday he does not believe there’s any hope for the bill to clear the Senate.

“Republicans have definitively sided with Donald Trump,” Murphy said, according to ABC News. “They've decided they want to keep chaos at the border because it is a political winner for them.”

He also called Republicans "a nightmare" to work with: "They are a disaster right now. How can you trust any Republicans right now? They told us what to do. We followed their instructions to the letter. And then they pulled the rug out from under us in 24 hours."

On Monday, Trump wrote on Truth Social that only “a fool, or a Radical Left Democrat, would vote for this horrendous Border Bill. 

“This Bill is a great gift to the Democrats, and a Death Wish for The Republican Party,” Trump said. “It takes the HORRIBLE JOB the Democrats have done on Immigration and the Border, absolves them, and puts it all squarely on the shoulders of Republicans. Don’t be STUPID!!!”

In a dramatic turnaround, Leader McConnell recommended to GOP senators in a closed-door meeting Monday night that they vote against the first procedural vote Wednesday, according to two people familiar with the meeting who were not authorized to talk publicly about it and spoke anonymously to The Associated Press.

It came just hours after the Kentucky Republican had urged colleagues on the Senate floor that “it’s now time for Congress to take action.” But McConnell has struggled to marshal his conference to support the package of $118 billion package of border enforcement policy and funding for Ukraine, Israel and other U.S. allies.

This wave of opposition prompted McConnell to recommend to Republicans behind closed doors Monday night that they vote against cloture on the motion to proceed to the bill this week, according to multiple attendees — effectively halting the effort in its tracks and throwing new aid to Ukraine into serious jeopardy.

In a statement Sunday, McConnell said the bill offered “direct and immediate solutions to the crisis at our southern border.”

At a news conference Tuesday, a group of Senate Republicans hammered McConnell over the deal, which Sen. James Lankford, R-Okla., negotiated on behalf of GOP members.

Sen. Mike Lee, R-Utah, complained that GOP members were kept in the dark about the negotiations.

“When you allow someone to negotiate on behalf of the larger group, the Senate Republican Conference, and for whatever reason, those in charge of the negotiation and directly involved in them didn't want to share details and text along the way, a gulf can develop between the negotiators and those on whose behalf they're negotiating — a gulf so wide that when it finally comes out, the reaction is not at all what either party wanted,” he said.

Said Sen. Ted Cruz, R-Texas: “'I’m angry. I'm angry that the Democrats want this human suffering to continue and I'm angry at our own Republican leadership for going along with it in a terrible bill.”

Cruz added that he thinks “leadership is massively out of touch with Republican voters.”

At Tuesday's Senate GOP leadership conference, McConnell and his cohort heaped praise on Lankford, with the Kentucky Republican hailing him for doing a "remarkable job negotiating with the other side."  

Meanwhile, GOP leaders in the House argued Tuesday morning the legislation would “only worsen the crisis at our border.”

“They did not send us a border security measure. They didn’t,” said Speaker Mike Johnson, R-La., who previously called the legislation “dead on arrival.” “They sent us a supplemental funding proposal that has immigration reform but not real border security reform. And so that's why it's a nonstarter.” 

Johnson said he opposes a provision that would give work permits to asylum seekers while they await rulings on their claims, arguing that would hurt American workers and incentivize migrants to head to the border. 

The speaker said a clause that would allow asylum seekers to be released from physical custody “endorses the Biden administration's catch-and-release policy.” And Johnson claimed a provision that would trigger a mandatory shutdown of asylum claims at the border is “riddled with loopholes,” including giving discretion to the homeland security secretary. 

The shutdown would be implemented when an average of 5,000 migrants are encountered at the border over seven consecutive days, or 8,500 on a single day. The House is expected to vote Tuesday on impeaching Homeland Security Secretary Alejandro Mayorkas, whom Republicans are attempting to charge with “willful and systemic refusal to comply with the law” and “breach of public trust.”

“Of course, this administration has shown the American people that it will exploit any measure to keep the border open,” Johnson said.

The $118 billion deal also includes assistance for Ukraine in its war against Russia and Israel in its conflict with Hamas. 

The Pentagon has run out of money for Ukraine. The agreement includes $60 billion for Kyiv.

“The clock is ticking every week, every month that passes,” Biden said. “Without new aid [for] Ukraine means fewer artillery shells, fewer air defense systems, fewer tools for Ukraine to defend itself against this Russian onslaught. Just what Putin wants.”

The deal also would send $14 billion in military aid to Israel and provide humanitarian assistance to civilians in Ukraine in the Gaza Strip.

The Associated Press contributed to this report.