The European Union of Jewish Students was thrown out of the conference after taking part in demonstrations against the Iranian president.
Its accreditation and that of its 100 participants was withdrawn for the vociferous way they showed their anger at Mr Ahmadinejad’s speech.
Among the group were Jewish students from Britain who were part of a political task force co-ordinated by Union of Jewish Students campaigns director Yair Zivan.
He said: “We were watching from an adjoining room but the UN stopped the translation of the speech. Then we tried to get into the main hall behind American lawyer Alan Dershowitz, who was in the room, but were stopped by guards. A security guard asked me to leave the building. He started pushing me and then grabbed my accreditation and ripped it off.”
Mr Zivan got his accreditation badge back on Tuesday but later that day the EUJS was told its entire accreditation had been withdrawn. Jewish students also took a leading role in a major demonstration about Darfur. “It was very important to show everyone here that our campaigns are not just about Jewish issues”, said Mr Zivan.