Republicans have blocked a bipartisan bill to tackle the US border and provide aid to Ukraine and Israel - succumbing to pressure from Donald Trump who wants to attack Democrats over immigration as he seeks another term as president.

Having spent months negotiating the legislation, that many Republicans just weeks ago admitted met more of their demands for tackling illegal immigration than any previous bill, senators voted 49-50, largely along party lines.

Because the measure required 60 votes to advance it did not do so, leaving Democrats quick to attack Republicans.

Joe Biden was among the first to do so, saying at a fundraising event in New York he “never thought I’d see something like we are seeing now”.

“[Republicans are] walking away because they’ve got Donald Trump calling and threatening them,” he added.

The $118 billion package would have provided extra resources for the US’s southern border and tightened requirements for those seeking to enter the country. It would have also provided military aid for Israel and Ukraine, the latter cause in particular being one the US president has found him increasingly isolated on as the conflict has entered its third year.

Republicans had in just the last few weeks turned against the bill because Mr Trump had made clear he did not want to give Mr Biden a “win” on the border in an election year.

As it is, Democrats are vulnerable on the issue of immigration, which is one of the reasons Mr Biden agreed to so many of the Republican demands.

But Mr Trump got his way, a victory that was made clear when House Speaker Mike Johnson said Republicans in the House of Representatives would not even consider the measure and that it was “dead on arrival”. He said Republicans would now look to push stand-alone bills to fund Israel and the border.

On Monday, Mr Trump tore into the measure on social media, just hours after the text of the proposed legislation was made public.

“Only a fool, or a Radical Left Democrat, would vote for this horrendous Border Bill, which only gives Shutdown Authority after 5000 Encounters a day, when we already have the right to CLOSE THE BORDER NOW, which must be done,” he said.

Four Republicans voted to advance the bill, including lead negotiator James Lankford, as well as Susan Collins, Mitt Romney and Lisa Murkowski. Five Democrats, including progressives Bernie Sanders and Elizabeth Warren, who thought it was too tough for would-be migrants, voted against it.

“Some have been very clear with me they have political differences with the bill,” said Mr Lankford. “They say it’s the wrong time to solve the problem, let the presidential election solve the problem.”

Senate minority leader Mitch McConnell initially supported the bill but then moved against it.

“Things have changed over the past four months, and it’s been made perfectly clear by the Speaker he wouldn’t take it up even if we sent it to him,” he said this week.

Majority Leader Chuck Schumer harshly criticised Republicans over the about-face.

“Why have Republicans backed off on border when they know it’s the right thing to do,” he said. “Two words: Donald Trump.”