Donald Trump has told a group of wealthy donors that he will crush pro-Palestinian protests on university campuses if he is returned to the White House.

The former president and presumptive Republican nominee called the demonstrations against Israel’s war in Gaza part of a “radical revolution” and promised the predominantly Jewish donors that he would set the movement back 25 or 30 years if they helped him beat Joe Biden in November’s presidential election.

“If you get me re-elected, we’re going to set that movement back 25 or 30 years,” Trump replied, according to the Washington Post, which first reported the event.

Trump also said his administration would expel any foreign students found to be taking part in the protests, which have recently taken the form of tented encampments in colleges across the US.

Addressing the meeting in New York on 14 May, Trump heard one donor complain that many of the students and faculty academics taking part in the protests could, in future, hold positions of power in the US.

He praised New York police for clearing the encampments at Columbia University and said the approach should be emulated by other cities, adding: “It has to be stopped now.”

Republicans have increasingly sought to make the campus protests an election issue, depicting them as a manifestation of “chaos” rampaging unchecked on Biden’s watch.

Congressional Republicans have staged a series of hearings on Capitol Hill to highlight the trend, focusing on reports of antisemitism among protesters and alleging multiple failures of university presidents to combat it.

In the latest hearing last week, GOP members of the education and the workforce committee assailed the presidents of Northwestern and Rutgers universities for negotiating voluntary dismantlements of the encampments, rather than calling in the police, as advocated by Trump.

In further remarks to the donors, Trump performed an apparent U-turn on Israel’s offensive in Gaza after months of equivocating by saying that he supports the country’s right to continue its “war on terror”.

He has previously said Israel is “losing the PR war” with its actions in Gaza. More than 36,000 Palestinians have so far been killed in an operation originally launched in retaliation for last October’s murderous assault by Hamas, which resulted in around 1,200 Israelis being murdered and another 253 being taken hostage.

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Speaking to the mass-circulation Israel Hayom newspaper in March, Trump said: “You have to finish up your war … You gotta get it done.” He has also said Israel should “get back to peace and stop killing people”.

In his donor meeting – which he joked was attended by “98% of my Jewish friends” – Trump reportedly failed to mention the name of Benjamin Netanyahu, Israel’s prime minister, who he resents for recognising Biden’s victory in the 2020 election and has not spoken to since.

But he boasted of his policies towards Israel, namely the decision to move the US embassy from Tel Aviv to Jerusalem and the recognition of the Israeli annexation of the Golan Heights, which Israel took from Syria in the 1967 six-day war.