Student zealots will be banned from censoring controversial speakers on campuses following the first ministerial intervention on free speech in 30 years.

Sam Gyimah, the universities minister, has announced tough new guidance which will see institutions disciplined if they allow valid debates to be shut down.

He vowed to stamp out the 'chilling' trend of speakers being blocked from campuses simply because there is institutional hostility to unfashionable views.

Student zealots will be banned from censoring controversial speakers on campuses, such as when Jacob Rees-Mogg scuffled with protesters in Bristol

Protesters stormed a university hall where he was due to give a speech - before calling him a 'nazi', 'fascist' and 'racist'

It will be the first government intervention on the issue since the free speech duty was imposed on universities as part of the Education Act in 1986.

The new guidance will state that all speech must be welcome at universities, as long as it does not violate existing laws – for example, on encouraging terrorism.

Sam Gyimah, the universities minister, has announced tough new guidance which will see institutions disciplined if they allow valid debates to be shut down

Any institution in breach of the rules may be named, shamed or even fined by the new Office for Students (OfS) regulator, which also has the power to deregister universities.

It follows a number of high profile cases of attempts by student unions to censor feminists, Tory politicians, gay rights activists and even race campaigners over concerns they had 'offensive views'.

Union officials claim they must 'no-platform' anyone who might say something controversial because they have a duty to protect the feelings of students and provide 'safe spaces'.

But Mr Gyimah said a free exchange of ideas must be integral to universities and warned some people were shutting down views to suit 'their own ends'.

Today he is chairing a private summit with university bosses, regulators, union officials, experts and civil servants to consult on what form the guidance will take.

He said: 'A society in which people feel they have a legitimate right to stop someone expressing their views on campus simply because they are unfashionable or unpopular is rather chilling.

There is a risk that overzealous interpretation of a dizzying variety of rules is acting as a brake on legal free speech on campus.

'That is why I am bringing together leaders from across the higher education sector to clarify the rules and regulations around speakers and events to prevent bureaucrats or wreckers on campus from exploiting gaps for their own ends.'

Masked thugs invaded a talk organised by a King's College London free speech society last night before setting off smoke bombs and attacking security guards

The self-proclaimed 'antifascist' protesters forced their way into the lecture hall and grabbed the speakers' microphones, smashing windows, and leaving notes threatening the moderator

Student union officials trying to stifle free speech often claim that guidance from the Charity Commission requires speakers to go through rigorous vetting.

But Mr Gyimah said his new rulebook will override any existing guidance from other bodies, which he branded 'murky'.

Victims of campus zealots Nov 2015: Students tried to stop Germaine Greer from speaking at Cardiff University, claiming she was transphobic. Feb 2016: NUS officer Fran Cowling wanted Peter Tatchell banned from speaking at a Canterbury Christ Church University debate after he spoke in favour of free speech. Oct 2017: Linda Bellos had an invitation to address a Cambridge University feminist society revoked because she admitted that she would be ‘publicly questioning trans politics’. Feb 2018: Students shouting ‘No platform for Tory scum’ tried to stop Jacob Rees-Mogg from speaking at an event at the University of the West of England, Bristol. Mar 2018: Students stopped a talk by a Right-wing author and an anti-feminist YouTube star at King’s College London. Advertisement

He said it would signal a new chapter for free speech on campus, ensuring future generations of students get exposure to stimulating debates and a diversity of viewpoints.

Sir Michael Barber, chairman of the OfS, which will take part in the summit, said: 'Our universities are places where free speech should always be promoted and fostered.

'That includes the ability for everyone to share views which may be challenging or unpopular, even if that makes some people feel uncomfortable.

'The Office for Students will always encourage freedom of speech within the law. We will never intervene to restrict it.'

Alistair Jarvis, chief executive of Universities UK, which represents vice chancellors, said: 'Universities are committed to promoting and protecting free speech within the law.'

Other organisations involved in today's summit include the Home Office, the Charity Commission, the National Union of Students, and the Equality and Human Rights Commission.

The guidance will be formulated in consultation with these stakeholders and published in due course.

In most cases, student unions and societies rather than the universities themselves have been 'no-platforming' speakers.

While these organisations are to some extent independent of universities, vice chancellors will still have a duty to force them to keep to the guidance while operating on campus.