Trinity College faces a bill of at least £24,000 to restore its portrait of Lord Balfour, following vandalism by activists from Palestine Action in March 2024.

Insurance correspondence obtained by the BBC via Freedom of Information requests shows that while the College declined to disclose the full restoration assessment, it confirmed: “The overall cost of the restoration is approximately £24,000.”

The early 20th-century painting by Philip Alexius de László was slashed and sprayed with red paint in an incident which was filmed and shared online.

Palestine Action, proscribed as a terrorist organisation by the government last month, claimed responsibility.

The group justified their actions on Instagram by claiming that the Balfour Declaration “began the ethnic cleansing of Palestine by promising the land away – which the British never had the right to do.”

Following the incident, Trinity College issued a statement regretting “the damage caused to a portrait of Arthur James Balfour during public opening hours,” confirming that police had been informed and an investigation was underway.

However, in March this year, Cambridgeshire Constabulary closed its investigation into the incident without identifying any suspects.

A spokesperson said: “A thorough investigation was carried out but the investigation has now been filed pending any new information coming to light.”

This month, the right-wing campaign group Great British PAC published an open letter urging Trinity to pursue further action in response to the incident.

Trinity College was contacted for comment.