The union which represents British academics has been accused of "hurting Jews" by proposing to reject a widely-used definition of antisemitism on the grounds that it stifles debate on Israel.
A resolution tabled for debate at its congress in Harrogate next weekend by the national executive of the University and College Union - which has been at the forefront of the boycott campaign against Israel - challenges the definition of antisemitism used by, among others, the National Union of Students.
UCU leaders claim that the description of antisemitism, drawn up several years ago by a European Union body known as the EUMC "confuses criticism of Israeli government policy and action with genuine antisemitism and is being used to silence debate about Israel and Palestine on campus".
According to the EUMC definition, antisemitism can take the form of denying Jews' right to national self-determination, applying double standards to Israel and comparing it with the Nazis.
But the document is also clear that using the same standards of criticism for Israel as for other countries does not constitute antisemitism.
The Community Security Trust's Mark Gardner said: "It proves, once again, that the UCU's executive are political extremists who care only about their ideological wars, including obsessively hating Israel and condemning mainstream political attempts to protect Jews from antisemitism."
The resolution, he said, would "comfort antisemites and hurt Jews".
A spokesman for the anti-boycott Fair Play Campaign said: "By attacking the working definition of antisemitism used by NUS, UCU is once again proving that Britain's students are more mature, more progressive and more committed to fighting racism then their increasingly extreme lecturers."
The UCU, asked to explain the reasons behind the resolution and provide evidence of suppression of debate about Israel, would say only that it expected "robust examination of motions in a whole host of areas".
The executive resolution also calls for "open debate on campus concerning Israel's past history and current policy, while continuing to combat all forms of racial or religious discrimination".
Four years ago UCU was forced to abandon attempts to embargo Israeli institutions after being warned that it risked legal action for racial discrimination. But only last year the congress expressed general support for boycott and sanctions against Israel.
NUS president Aaron Porter said, before the NUS vote on Israel, that the EUMC definition had been adopted by NUS to set boundaries of what constitutes antisemitism, while still allowing for legitimate debate and criticism of Israel. "All students have the right to study, socialise and live free from racism, fear and intimidation."
Professor David Feldman, director of the Pears Institute for the Study of Antisemitism at London's Birkbeck College, said: "If the UCU leadership believes these resolutions provide a benchmark for regulating debate on Israel, it is going to be disappointed. There is no consensus on where legitimate criticism of Israel ends and where antisemitism begins."