US President Donald Trump has drawn criticism from Jewish groups after he used an antisemitic term at a rally.

Trump described some bankers as "Shylocks" at the event in Iowa. He said afterwards he did not realise it was considered offensive. Shylock is a ruthless Jewish money lender in Shakespeare's play The Merchant of Venice.

The Anti-Defamation League (ADL), a Jewish anti-discrimination monitor, said the president's use of the slur was "very troubling".

Former US President Joe Biden used the word Shylock while he was vice-president, later acknowledging it was inappropriate.

At Thursday's rally in Des Moines, Trump was celebrating the passage of his budget bill through Congress this week.

"Think of that: No death tax," he said. "No estate tax. No going to the banks and borrowing from, in some cases, a fine banker - and in some cases, Shylocks and bad people."

As the Republican president returned on Air Force One to Washington DC after the rally, he was asked by reporters about his use of the term. He said he was not aware it was seen as antisemitic.

"No, I've never heard it that way," the president said. "To me, Shylock is somebody that, say, a money lender at high rates.

"I've never heard it that way. You view it differently than me. I've never heard that."

Congressman Daniel Goldman, a New York Democrat, called Trump's remarks "blatant and vile antisemitism, and Trump knows exactly what he's doing".

The ADL said in a post on X: "The term 'Shylock' evokes a centuries-old antisemitic trope about Jews and greed that is extremely offensive and dangerous.

"President Trump's use of the term is very troubling and irresponsible."

Amy Spitalnick, head of the Jewish Council for Public Affairs, said on X the remark was "deeply dangerous".

"Shylock is among the most quintessential antisemitic stereotypes," she said. "This is not an accident.

"It follows years in which Trump has normalized antisemitic tropes and conspiracy theories."

Trump's allies have previously brushed off any suggestion that he is antisemitic, pointing out his staunch support for Israel and that close advisers of his, including Stephen Miller and Steve Witkoff, and his son-in-law, Jared Kushner, are Jewish.

The president's administration has launched a campaign to weed out antisemitism on college campuses, withholding federal funding from some institutions, such as Harvard, and taking steps to deport pro-Palestinian activists who are in the US on student visas.

Then-Vice-President Biden, a Democrat, used the term Shylock in 2014 when addressing a legal group.

"People would come up to him and talk about what was happening to them at home in terms of foreclosures," he said, referring to his son's experiences serving in Iraq, "in terms of bad loans that were being - I mean, these Shylocks who took advantage of these women and men while overseas."

Following uproar, Biden said "it was a poor choice of words".