Members of the University and College Union defied a warning from their leadership and passed a motion in support of boycotting Israel at their annual congress in Bournemouth.

They voted to support “the Palestinian call for a boycott, disinvestment and sanctions campaign”.

But the union’s executive had warned that it would be declared null and void following legal advice that the resolution would be unlawful because “it is likely to be viewed… as a call to boycott Israeli academic institutions”.

A second motion called for a conference to investigate the “lawful implementation” of a boycott strategy “including an option of institutional boycotts”.

The congress also voted to hold a one-day conference on antisemitism, but rejected an amendment calling for an investigation into resignations from the union “apparently in connection with perceptions of institutional antisemitism”.