Sen. James Lankford talks to reporters as he makes his way to a meeting at the US Capitol on February 5, in Washington, DC.

Senate Republicans blocked a major bipartisan border deal and foreign aid package with assistance for Ukraine and Israel in a key vote on Wednesday amid a torrent of attacks on the bill by former President Donald Trump and top House Republicans.

The failed procedural vote amounts to a stunning rebuke by Senate Republicans of a deal that would have enacted restrictive border measures and was crafted in part by one of their own members – James Lankford of Oklahoma, one of the chamber’s most conservative senators. Republicans had demanded that border security be part of the bill, but have now rejected the deal after pressure from Trump, who is making the border a central campaign issue in his race for the White House.

The outcome leaves aid for Ukraine and Israel, two key US allies, in jeopardy at a critical time. In the aftermath of the vote, lawmakers will face increasing pressure to pass foreign aid on its own without any border provisions – an uncertain prospect as some Republicans are opposed to further aid to Ukraine.

The Senate voted Wednesday evening to take the first step toward debating the foreign aid package with the border security provisions stripped out. But a key test vote looms ahead, and it is unclear if that will succeed as Republicans are demanding an agreement to have their amendments to the underlying bill considered.

“We will recess until tomorrow and give our Republican colleagues time to figure themselves out,” Senate Majority Leader Chuck Schumer said Wednesday evening. “We