Student leaders are worried that the hard right is gaining ground in universities after evidence of British nationalist groups moving in on several campuses.
Leeds, Leicester, Derby and Nottingham universities are being targeted by racist groups such as the Patriotic Students' Association, Students for Britain and the National Student Front.
At Leeds University, a meeting of the Free Speech Society, led by rightwing activist Mark Collett, was cancelled after complaints from anti-Nazi groups.
A university statement said: "As organisers of a potentially controversial meeting, the Free Speech Society has failed to give adequate notice so that... security arrangements can be put in place."
The society campaigned for Leeds students' union to drop its "no platform for racists" policy but its motion was defeated.
Anti-fascist campaigners claim that Mr Collett, described on the British National Party's website as "a leading member of the British Students' Association", hijacked the Free Speech Society to pursue a hard-right agenda. But Mr Collett denied this and said: "Our society is a broad church."
Nationalist groups are also organising on other campuses. Marissa Sakol, campaigns organiser for the Union of Jewish Students, said there was evidence of activity by hard-right groups at Midlands universities including Leicester, Derby and Nottingham. The National Student Front mentions a new unit established at Leicester University on its website.
Mr Collett told The THES : "As an active nationalist, I have seen a huge growth in nationalism at Leeds University and across the country as a whole. The BNP is gathering huge momentum at Leeds and in many other universities as students are now starting to see past the media smoke screen."
NUS president Owain James said he was taking the issue very seriously. "Wherever they organise, attacks increase," he said. "We are going to ensure that they have no platform in student unions."