A group of pro-Israel lawyers have “demanded damages” from City, University of London over a cancelled talk by the Israeli ambassador, blaming it on the institution’s failure to make special security arrangements.

UK Lawyers for Israel (UKLFI) wrote to the university’s president, Sir Paul Curran, this week to demand “a public admission… that it acted illegally” in refusing to provide security officials with handheld metal detectors.

The Union of Jewish Students (UJS) and UKLFI have claimed that last month’s planned talk by Mark Regev, the Israeli ambassador to Britain, was cancelled on police advice.

UKLFI also demanded that the university take steps to “secure freedom of speech at meetings of its Israel and Jewish Societies”, as well as damages to be donated to charity.

But the university hit back, saying the decision to abandon the talk was made by the embassy, and that “there was insufficient time to agree and arrange appropriate security measures”.

A university spokesman said: “City is taking legal advice regarding the letter it received from UKLFI and will be responding to the letter in due course.

“The University had been working with our Students’ Union on appropriate security measures to enable the event to take place, while being conscious of the need both to protect freedom of speech and discharge our duty of care for the safety of our students and staff.

“We understand that the Students' Union has resumed discussions with the aim of holding the event, with appropriate security measures.

“City has an absolute commitment to securing free speech within the law on campus and the University will take all steps which are reasonably practicable to achieve this.”

The university also supported its Students’ Union’s refusal of a request to supply organisers with a list of ticket holders “so that they could be vetted” ahead of the event.

The Metropolitan Police said that officers provided security advice for the event, but that the decision to call the talk off was a matter for organisers and the university.

The force said it would not discuss the specifics of the advice it gave.