US President Donald Trump has announced that Washington will stop providing $4 billion in annual funding to Israel after the end of this year.

Trump made the announcement while speaking on Fox News' Fox and Friends, after voting in the midterm elections began.

"Now, as far as paying Israel, Bibi Netanyahu and I have made a deal that we give Israel $4bn a year, and we made a deal months ago that we're stopping," Trump said.

"We've already agreed that by the end of this year we won't be paying Israel. Now we'll help Israel if they need it."

Trump said the decision was reached in an agreement with Israeli Prime Minister Benjamin Netanyahu, which he said was made months ago.

Asked why the US was halting the aid, Trump said: "Because they don't need it. If they did need it, I would say 'keep going.'"

It was not immediately clear what specific form of aid Trump was referring to. The US State Department did not immediately respond to a request for comment.

Military aid to Israel, and US political campaign contributions from Israel's backers to candidates, have been a flashpoint for both Democrats and Republicans this year.

Harsh public criticism of Israel by US political leaders in recent years marks a dramatic shift from decades of staunch bipartisan backing.

In July, the US House of Representatives defeated an amendment to cut off aid to Israel, despite nearly half of Democrats supporting it. The House voted 314 to 104 to defeat the measure, which had been offered as an amendment to a State Department spending bill by outgoing Representative Thomas Massie of Kentucky, an outspoken Republican critic of US policy in the Middle East.

Trump also said some politicians were using the funding to criticise Republicans.

Former Republican congresswoman Marjorie Taylor Greene commented on the announcement on X, writing: "Amazing how being on the verge of Republicans getting wiped out in the midterms changes hearts and minds."

"Trump getting permission from Netanyahu to end annual aid to Israel isn't going to change today's election results," she added.