US Congress failed to pass a $110 billion (€102 billion) package of wartime funding for Ukraine and Israel as well as other national security priorities, a move Senate Republicans had threatened to do all week.
The US president warned the move by Republican senators could have dire consequences for Kyiv and may be seen as a gift by Russian president Vladimir Putin.
“They’re willing to literally kneecap Ukraine on the battlefield and damage our national security in the process,” Mr Biden said.
Mr Biden, however, signalled that he is open to working on the border policy changes Republican politicians want to see first.
He stressed that he is willing to “make significant compromises on the border” if that is what it takes to get the package through US Congress.
Republicans have argued the record numbers of migrants crossing the southern border pose a security threat because border authorities cannot adequately screen them.
They also say they cannot justify to their constituents sending billions of dollars to other countries while failing to address the border at home.
So far, senators have agreed on raising the initial standard for migrants to enter the asylum system.
But they have been at odds over placing limitations on humanitarian parole, a programme that allows the executive branch to admit migrants without action from Congress temporarily.
“We need to fix the broken border system. It is broken,” the president said, adding that he is “ready to change policy as well”.
He did not name specific policy proposals and accused Republicans of wanting a political issue more than bipartisan compromise.
Oklahoma Republican senator James Lankford, who has been leading Senate negotiations over border policy, said it seemed like the president is “ready to be able to sit down and talk”.
Senators of both parties acknowledged they would need to move quickly if a deal was to be struck as US Congress is scheduled to be in Washington for just a handful more days before the end of the year.
“When deadlines come, everybody’s undivided attention is there, and we realise:’ OK. Now it’s time to actually solve this,'” Mr Lankford said.
Democrats involved in the negotiations also said a direct hand from the president, as well as from Senate Republican leader Mitch McConnell, could be helpful.
“This kind of thorny, difficult problem is exactly what Joe Biden and Mitch McConnell have worked on before. And we could use their help and their leadership on this,” said Democratic Senator Michael Bennet, another negotiator.
The White House, meanwhile, has sounded the alarm about what would happen if the Senate does not approve more international aid funding soon, adding Ukraine’s military would be stalled or even overrun. – AP